There is significant update material for the ELH available on the WotC website, including updates of all the epic feats and monsters. iirc they hit up the spells too.
Also, there is a pittance of epic support in the Complete books and the environment books (both Frostburn and Sandstorm have a couple of epic spells in them, for instance).
It seems to me that WotC is giving epic material roughly the same level of support as they are psionics, though that looks like it's about to change with the release of Complete Psionic in a few months. Maybe a 'Complete Epic' book is in the works? If not, maybe it should be?
And if it is, hopefully they will have suggestions as to how to work around the ridiculous amounts of money assumed to be thrown around in epic play- that is, imho, the worst aspect of epic rules. Who really finds a horde of 1.75 million gold just so the party wizard can research a single epic spell??