Can't speak for the autographs specifically but the prices are very reasonable(maybe too low). But, I did look up and see that they an UACC Registered Dealer #RD050.
I have to say that the music signatures are a mixed bag. Some are real and some are fake. For example, iron maiden somewhere in time is fake and iron maiden brave new world is real. So be very cautious if you are looking to buy something from this website.
I only had a look at the music items, and it's certainly a mixed bag, with lots of obvious fakes (mostly top end) and authentic items (mostly low end) as well.
From some artists (e.g. AC/DC, Iron Maiden) there are both authentic and horrible fake items.
The prices seem to be all over the place regardless of authenticity, so it's possible the seller is honest, but clueless (and as such shouldn't really be in the autograph business).