I recommend Old House Heirlooms!
They offer some great bulbs and the prices aren't bad either especially if you are looking for limited quantities.

Here is a link that might be useful: Old House Heirlooms

Depends on what you are looking for.

For rare, unusual and/or highly perishable, nothing can beat Odyssey Bulbs. Quality and customer service are both out of this world. Quantity discounts are quite generous and most orders qualify for free shipping. Prices are actually reasonable considering much of the material is available nowhere else.

For rare forms of snowdrops sold "in the green," Carolyn's Shade Gardens and The Temple Nursery have been absolutely wonderful.

Brent and Becky's is great for the more "common" (but still wonderful) bulbs. I have had nothing but good experiences with them.

Van Engelen's selection is much more limited compared to the above, but prices are very good. I have purchased many things from them and overall quality is very good, although I do tend to find some bulbs have a slightly higher percentage of dry rot or soft nonviable bulbs compared to Brent and Becky's (a handful of bulbs per 100 vs. very few or none for Brent and Becky's). Still, a very good source for the price.

I have mixed feelings about Old House Gardens. I really, really want to love them, but I just can't. I think many of their offerings are insanely expensive and they are not necessarily of the best quality. However, their customer service is superb and they do stand behind their product. The worst daffodils in terms of lack of vigor and poor performance in my garden all came from Old House, but their winter aconite tubers tend to be healthier and more viable than from other sources.

Odyssey Bulbs offers 1 (one) Gladiolus imbricatusfor $9. I'd say they're for collectors only.

Iris_gal, I am not in any way trying to be confrontational, but do you know of another source for Gladiolus imbricatus? As far as I know, Odyssey is the only supplier in the U.S. For a rare bulb unavailable elsewhere that is almost 100% likely to be true to name and properly handled, in addition to orders over $30 qualifying for free shipping and volume discounts beginning at $50, I am not sure that is really expensive overall (in my opinion).

It all depends on what we are looking for and what we like to fill our gardens with. Different strokes for different folks, lol! :-)

Ispahan