No.I'm afraid the odds are stacked against you with the maples.

They will die inside--it might take a few months, but they won't survive. Giving them plenty of water and misting them indoors will kill them much more quickly. Inside, the plants won't receive nearly enough light. That means they won't be using much water. Additionally, maples need a cold dormancy period--which even if you keep them outdoors, is going to be difficult to provide. If they're kept indoors now, they will not be prepared for winter, as shortening daylight hours are the trigger for trees to prepare for winter. Inside, the plant will have no "idea" that it should be preparing.

Some folks have overwintered maples in hotter zones in refrigerators. I haven't heard of anyone doing this for more than a few years. Using a refigerator doesn't set the plant up for dormancy. It merely chills the plant (in very arid air--which is a problem in itself).

Here is a link that might be useful: Phoenix bonsai society

Even if you were still back in the cooler climate of Ohio, I wouldn't recommend a Norway maple as a bonsai.
The have large leaves like many other native maples(Red, sugar, silver etc). The leaves don't reduce well and the internodes are long.
Bottom line, maples in general are very difficult in your climate.
If your interested see link below for some other alternatives

Here is a link that might be useful: Phoenix Bonsai

I don't believe that you have seen the native trees that are grown as bonsai in Arizona, horrible, hideous, thorny monsters that have no leaves to speak of and barely resemble trees including, Texas Ebony, Mesquite, Palo Verde, and Ironwood. I despise each and every one of them! I'd also like to tell you that one of the most popular garden trees here is Phoenix is the Chinese Elm. Another favorite is the Mountain Ash. I'd also like to tell you that I currently keep boxwood, arborvitae, blue juniper, and crape myrtle outdoors, and indoors I keep ginseng, horse chestnut, and ginkgo biloba. Once, I even got a Green Mound Juniper to live indoors here for over a year!

So, with that in mind, what do you suggest I do now?

There are a few good bonsai candidates for your clime. These are a few:

Strawberry Tree (Arbutus unedo)
Ficus
Olive
Dwarf myrtle
Some varieties of grape vines
and you already mentioned chinese elm.

There are also numerous tropicals that you can grow indoors. If you are determined to grow more traditional species, then you can set up an indoor grow area, but it can be costly. You will have to be able to provide for your plants' light and temperature needs.

Personally I would probably give up on the norway maples. They're really meant for a different climate and, as another post pointed out, the leaves don't reduce well. It would be impressive to get them below 2". I would go ahead and get some chinese elm and see what you can do with them.

I guess I'm scratching my head here. Who said you have to use natives (although they offer some of the toughest material available to you and the species you've mentioned can be quite nice bonsai. Texas ebony in particular.)Pinyon, ponderosa, lodgepole pine have all been used spectacularly as bonsai. They might work for you too.

Bougainvillea, olive (olea species), chinese elm, ficus, caliandra, schefflera all make tremendous bonsai when decent stock is used.

The link below leads to some species used in Texas. ...Some are native, some are tropical. Most are probably suitable for AZ, Note the Texas ebony.

You can try maple all you want. Most any species of it won't stand up to your climate. You're going to have to let go of it...

A juniper indoors for a year is great. It will be even greater if you can keep it going for two or three. Beyond that, you get bragging rights as one of the few people that's able to keep them indoors successfully. How long ahs the ginko been inside?

Here is a link that might be useful: Texas bonsaigarden

It can be done, however, the vast VAST majority of "indoor" bonsai junipers die, as do most other temperate zone plants when kept inside.

Got any details on how long the plants were kept inside? Any details on the secret to keeping them indoors? Got any actual live trees to show?

"Pinyon, ponderosa, lodgepole pine have all been used spectacularly as bonsai"

That is very true, however, none of those trees are sold anywhere in Arizona, they grow wild, but they are only in the national parks and forests here where it is illegal to collect wild ones (or anything from the forest for that matter, not even rocks can be taken out)

"Bougainvillea, olive (olea species), chinese elm, ficus, caliandra, schefflera all make tremendous bonsai when decent stock is used."

Bougainvillea have never held any appeal to me (although many varieties are available here), olive is a very common tree here, however, there are no nurseries that sell suitable stock for bonsai (all are already full size trees), besides, I am horribly allergic to olive blossoms. I would LOVE to get my hands on a suitable chinese elm, but once again, the only trees sold are already eight to nine feet tall and that would be a very long process to make one of those into a bonsai, also, they are extremely expensive (up to $300!) I already have several Ginseng ficus trees indoors, What is a caliandra?, and schefflera make very lousy bonsai, their leaves are too large and sparse, and they fair very poorly indoors here, and outdoors they do even worse.

"How long ahs the ginkgo been inside?"

Four months

"Got any details on how long the plants were kept inside? Any details on the secret to keeping them indoors? Got any actual live trees to show?"

Yes, the juniper was kept indoors from two years ago Father's day, until the following May. One of my secrets was not to over water it. I watered it once every three days and misted it every two. I kept it in the most "outdoor climate like" room of the house (my bedroom) which has a huge window and a small airvent behind the fan so the fan dissapates the cool air throughout the room and so does not blow on the tree. I also put it outside for an hour or so twice a week. Sorry, I have no live junipers to show, but I am currently finishing up a camera full of pictures of my trees, I should have them posted within two weeks.

There are web sites that will ship almost all the species you've said aren't available in Ariz., including the native pines. Brent Walston at Evergreengardenworks.com has hundreds of chinese elm stock trees--some for hundreds, most for less than $50. Andy Smith at Golden Arrow Bonsai (do a seb search for his website) sells legally collected ponderosa pine, black hills spruce and others. It is legal to collect alligator juniper and probably others in Ariz. also. A few clubs have done it--articles on collecting this species have appeared in the American Bonsai Society's Journal. Just requires getting the right permits and making the right connections. Bonsai clubs will help with this enormously.

Additionally, there is quite a bonsai community out that way. There are many sources in Calif. that have wonderful olives, black pines and the like. I would especially check on those sources.

The link below might help get you started.

Here is a link that might be useful: link to bonsai sources in Phoenix

I have seen a nursery in Flagstaff that usually has Black, White, Aleppo, Pinon and Ponderosa pine
in 3 gallon containers around Thanksgiving through Xmas. There is also a nursery in Sedona, if you
ever venture outthat way. Have you ever thought about raising Chinese Elm from seed? It loves the
strong sun here and will most likely get to a good size in about 2-3 years.

As for Schefflera making "lousy bonsai," as with most potential bonsai, it depends greatly on what you start with.

Schefflera can make absolutely stunning bonsai. See link. Is great stock inexpensive? No. It's more than $1.99 at the Walmart...

Here is a link that might be useful: Hawaiian Scheffs

No maples will survive very long indoors anywhere, least of all Arizona. They NEED freezing winter dormancy for months, or they can't continue to live.