If you want a Cobb cookbook look at Hairy Bikers' Cookbook and the followup. Pretty much everything in those books was cooked on a Cobb.
As to whether it's worth the cost for solo camping, it really depends on how much you like cooking and eating. I went for the CADAC rather than the Cobb because I'm generally wanting something quick when I get (back) to the campsite, rather than putting something in the oven for an hour or so.
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.