<a href="http://www.ezcosplay.com/" rel="nofollow">http://www.ezcosplay.com/</a> I've read a lot of good things about them but never purchased from them
<a href="http://www.hellocosplay.com/" rel="nofollow">http://www.hellocosplay.com/</a> I've read good things about them too
<a href="http://www.aliexpress.com/store/812718" rel="nofollow">http://www.aliexpress.com/store/812718</a> I've only bought from them once but it was very nice for how cheaply I paid.
I think it's hit and miss with Ebay. Make sure to read those reviews before purchasing
For lenses use <a href="http://www.pinkyparadise.com/" rel="nofollow">http://www.pinkyparadise.com/</a> I've never used them but my friend buys her prescription lenses from them because they are lie 20$ cheaper than the eye doctors but are the same quality. Plus like all the people on youtube get their lenses from here.
<a href="http://www.eshopcos.com/" rel="nofollow">http://www.eshopcos.com/</a>
FYI
This is the decent jacket my friend got, <a href="https://www.facebook.com/photo.php?fbid=10201224917624356&set=o.617602001599965&type=1" rel="nofollow">https://www.facebook.com/photo.php?fbid=...</a>
eBay is the way to go! They have extremely cheap wigs and outfits!
(as for circle lenses, I wouldn't go cheap, I use pinkyparadise.com)