hi jimmy, it may be a bit of a drive for you, but try snrc,
http://www.stoke-nitro.co.uk/s.n.r.c/index.html
its not dirt, but the best new astro track around, go onto their forum and see the track with its new extension
small table tops, doubles, triples, larger table top, raised table top corner, moguls, they have it all. superb drainage and 10mins drive off the m6.