Pedals for track

I'd be wary of buying shoes by mail order, especially from ebay. You don't want to find that the shoes don't fit after trying them out on the bike and being unable to return them.

I don't think you'll struggle to find shoes that fit. Most of the major brands do larger sizes, i.e. Sidi, Northwave, Mavic, Specialized. Shop around at this time of year, as shops sell off 2009 stock, and you'll probably find a good deal.

Are the shoes going to be used exclusively on the track?

Yes the shoes will be exclusively on track, i take your point on mailorder, specially since my feet are also very very wide, so definetly best to try them on first.

whats your opinion on these pedals, seems like the best of both worlds,
http://www.worldclasscycles.com/mks_exa_pedal.htm