Thanks!
For anyone specifically interested in SEO, I have spaces available on NonStopArcade.
NonStopArcade has over 2300 pages indexed in google and receives a very big majority of its traffic from google, so it does very in search engines and this really does help the sites that it links to.
The site receives 6000 – 7000 uniques / month now.
I am only adding a few more links to the site and all adsense will be removed to make it more se friendly and less ads for users, giving a higher CTR on the links as well 
Right Navigation Text Link – Static – £9.95 / month
160*600 Skyscraper – Sitewide static – £14.95 / month (Only ever 1 shown)
Header 468*60 – Rotation with 4 other banners – £9.95 / month
Right Navigation Button – Sitewide – 125*125 – £9.95 / month (Only ever 1 shown)
Game Sponsorship – £2.95 / Game / Permanent – Discount for purchasing 20+ Minimum of 5
If anyone is interested just post here or PM
Thanks to everyone that has purchasing links on my sites so far, I appreciate your support!