Dear Martin,
Some suggestions based upon a quick look.
1) Firstly can you darken the green font ? It is very difficult to read on my screen.
2) May I suggest that you open out the description of "Foreign" in books. This is too simplistic bearing in mind that there are some 2252 titles in there.
May I suggest the following sub-categories ?
North America
South America
Europe
Former Soviet Union
Asia and Pacific
Australia/New Zealand
3) DVD - Please do same as in (2) above
4) Clearance books, again please do as in (2) above as there are over 1000 railway titles on clearance which is an awful lot to look through, and I would imagine people do not have the time to trawl through that number.
5) Based on a quick back of the hand calculation and using a fast cable connection, to view that 1068 books shown would take 72 minutes continuous browsing. You can easily double that DVDs, full price books, etc
6) Turning now to Aviation, again similar comments apply in that section. My particular interest is in WW2 but this is not categorised and to search through everything would take something like 4 hours if my back of hand calculations are correct.
7) Aviation - May I suggest you look at some categorisation, maybe along the following lines ? :-
Historic aircraft
WW1
WW2
Post War
Modern
Sub categories I would suggest should be :-
UK
European
Former Soviet Union
USA
Middle East
Asia & Pacific
8) History - To avoid repeating myself you need to definitely categorise and sub-categorise this.
That is all I have time for but I think you get the central theme ?
PS nearly forgot. As someone has already pointed out, your basic search is way to simplistic and is in effect unusuable unless you come for a specific title (not checked up on that search by the way). You need to create a more detailed version I feel.
Hope this has not come across as too negative bearing in mind the hard work I am sure that many have put into this.