I just finished working on a project that was REST based using WCF technology. These are the resources our team referred to for gaining an understanding of REST (Not just from WCF perspective).
1)The REST-discuss group on Yahoo, provides excellent source of information for commonly encountered issues in REST design.(Sometimes even Roy Fielding answers user questions)
2)Programming WCF by Juval Lowy is a good book to understand WCF. Its concise and to the point "http://oreilly.com/catalog/9780596526993/"
3)If you want to know the internals of WCF, one of the best sources is Aaron Skonnard's service station "http://www.pluralsight.com/community/blogs/aaron/default.aspx".
4)If you would like to see REST from a platform neutral approach, then Sam Ruby and Richardson's book is best. "http://oreilly.com/catalog/9780596529260/"
5)To know all the esoteric concepts associated with WCF, Nicholas Allen's blog is great.
"http://blogs.msdn.com/drnick/ "
Hope this answers your question