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.
A day of all things motorhome and campervan. The show is held both in the main indoor arena and across the grounds. Catering, hot drinks and food options are available. Easy access to the site and free parking included. Win one of five pairs of day tickets