There are as many ways of building a pond or water feature as there are people who build, buy or contract the work out. There are some interesting ponds on the gallery section of this forum but I suggest you check out the Public Library in your area for some in depth research.

I have seen some delightful water features that I would love to add to what I have but there are limits to my creative madness such as money, time and physical problems. LOL! Everyone thinks their kind of water feature is the best. If this is mainly for the birds, they require a shallow basin or a flat rock the water can flow over to serve as a bathing area. If it is too fast moving or deep, they can drown. My first pond didn't have a good space for the birds to perch or bathe so they would deliberately set off my motion and heat sensitive water cannon and fly thorough the spray. It was a lot of fun to watch them but they used up a lot of water.

You do want to keep the birdseed a fair distance from the water since it would become contaminated very quickly and be high maintenance. I am assuming that is something you wish to avoid.

One thing you can look into is a pondless waterfall. It gives the advantage of moving water and the noise that distracts from traffic yet fits well in a small area. The maintenance is low.

Basic materials and equipment are a basin of some sort, it can be preformed, a half barrel, or it can be a flexible liner. Something to form a spillway can be made of stacked stones,pots, etc. You will need a pump of the right size and a filtering system to protect the pump. Check out Adam's filter. It is cheap and easy. I made one out of a Tupperware canister once. Then there is tubing to direct the water where you need it. The pump will likely come with attachments to make a fountain or you can buy those separately if that suits your fancy. I don't know how much or little you want to invest but I have seen kits that are very adequate for around $100 at places like Meijer, K-mart, Target, WalMart, Lowes, Home Depot and Menards. I saw some lovely pondless water features that were made from a large pottery jar that sat on rocks that hid the water tank.

There are lots of lovely plants to go into your water feature. Some plants like the water lily need more water depth than others but there are some that can be grown in relatively shallow water. Most are going to require lots of light to flower. The Library is going to have lots of books on water garden plants. The name to look for is Helen Nash but there are others who do a good job as well. Container plants around a water feature do very well.

Since the books can be expensive, you might want to wait to buy some until you find one you think is worth the price to you. I have several dozen myself, but I am a book fanatic. Sandy

Hi
To the above I'd add .You've made a good start by deciding what the primary purpose would be . Another step is how much space you want to devote to it. Where it would be located. If you want lilies or even most water plants the more sun the better..Fountains and lily pools combined
aren't necessarily exclusive but require a good design.
Consider your climate and winter care in advance particularly if you want to keep plants. Electrical connections,plumbing.
Look around the internet to eliminate designs that don't appeal to you. Shallow slow moving verticles are magnets for birds unless you want to attact herons or egrets. In that case add some very expensive fish . You'll have dozens in no time ,along with raccoons,stray cats and even kids lol. To build or to buy is a tough question.,depends on how handy you are, how elaborate the setup, choice of materials.
When you think about it the only difference is assembly. Which you'll have to do yourself anyway. Most kits are ridiculously expensive IMO. But does take a lot of guess work out of it. Good luck gary