Wouldn't you look for the brand/size that you want first? Then finding a site that sells it is the easy part. If you want to take a stab in the dark, I'd try some of the large online aftermarket car part stores like autoanything.com and jcwhitney.com
I have two sites that do custom CNC milled hub centric wheel adapter spacers. I'm away from my office, but if you pm me, I'll get you their contact. In the meantime, what is the hub diameter, wheel width and offset of the new wheels? I can give you some advice, as I just went through this.
Here they are. I bought mine from the 42draftdesign folks (you need to call them), but I've heard good things about the other guys (I've given you the online ordering link). Prices seem identical. Let me know if I can help otherwise.
By the way, adapters have new lugs built into them. 1.25-2" is way too much to use the original lugs--so the original lugs hold the adapter and the adapter lugs hold the wheel. Just make sure you still get hub centric adapters.