Getting an ordinary commercial slingshot is easy. Just punch your favourite model in a search engine and you'll find tons of shops, many selling worldwide. Gathering material to make a slingshot by yourself is just as easy - a wooden fork or board, a piece of metal rod and you're ready to go.
So much for the frame. But you'll soon find out that it is highly difficult to get good bands and cheap ammo! It depends on your country and the shops you have access to, but replacement bands and ammo are often as expensive as the slingshot itself. Spare parts are always a nice source for steady income. Your slingshot might last for decades, but ammo and rubber doesn't.
It is even more difficult to obtain good rubber for selfmade bands. I'm convinced that thin flat latex bands outshoot every other type of rubber yet employed on slingshots. Try to find that....but fortunately, I'll tell you some places to get the good stuff! Here we go:
I am not affiliated with any of the following retailers. I just know they are good and want to share this information.
You can often find good offers for marble or steel ball bulk packs on ebay. Trumark's bulk buy offer is also ok. For very good prices on bulk steel balls, go to RoyalSteelBallUSA. If you want plinking ammo for almost nothing, get a small syringe, cut off the "head" and use it to portion concrete which you roll into bullets. This way, you have uniform weight, and the ammo is surprisingly accurate.
Getting latex tubing is not too difficult. There are various sources, most can be easily found by using a search engine. Rubber tubing can be dipped or extruded, the latter being no good for slingshots. Try to get "mandrel dipped latex tubing". Sources I know are Hygenic , Primeline Industries and ReefscubaYou can also try other shops that sell speargun equipment.
The best flat latex is produced by Hygenic. Disadvantage is that they only sell it in very large quantities. There are other sources for flat latex, like Textrip, but they don't match the quality of Hygenic sheeting.Anyway, you have low chances to get rubber for under 100$ with any of these manufacturers. Another possibility is Theraband-style training band. It is not perfect, but still better than most types of tubular rubber.
Luckily, Bill Herriman is selling rubber and band assemblies. The bands are dual tapered flatbands made of Hygenic latex, with a soft leather pouch that has a mould in the middle. And, simply said, they are the best of the world. I tried lots of different bands, commercially, selfmade etc, but nothin came even close to the performance of these ! Mr. Herriman himself has won several National slingshot tournaments with them, and the bands he sells are made exactly like the ones he uses for tournament. They are compatible with the Saunders Wr Pro and the new Double Eagle and come in three power levels - target, express and magnum. Address is Bill Herriman, 707 Cardinal Drive, Kerrville, TX 78028