What can I sell these wheels for?

Bargain, I sold my 16's off my 2.8Q for £320.
It maybe just because you've set a buy it now. People seem to like the chance of a bargain with the auction. Setting a reserve or high start price just seems to put people off. I start low, then just use a couple of mates to hike the price if it looks like it'll go for stupidly low money.
 
To be honest I would say they are worth more like £150 - £200 as the tyres will want replacing by the sounds of it.
 
For around £250, you can get a set of 17" S3 Avus alloys on ebay, yours are 16", so I would aim around 150-200 mark, as suggested by Markb above /ubbthreads/images/graemlins/beerchug.gif
 
If all the tyres will need replacing, then they are worth no where near that price - you could be paying over £300 for new tyres - people will just spend a little bit more and buy some 2nd hand ones with good tyres. The wheels are mint as you say, but I reckon theyre gonna have to go for below £200.