Trains timetables from UK to eastern europe?

I can't find a website that gives me international train timetable from London to East Europe (particularly croatia). The only ones I find want me to manually breakdown my journey by finding London to Paris, Paris to Munich and Munich onwards etc...

Does anyone know how I can find out the most effecient route?

Try raileurope.com, if not them, I doubt that one single site will help ya.

Why haven't you BOUGHT a copy of Cook's RAILROAD TIMETABLES...? It's a red and white book and lists ALL the railroads and the times IN EUROPE... but you have to BUY it... on the other hand... you can take the book with you.

There are several rail planners that can handle the whole distance, but still, breaking your request is almost always needed.

http://www.raileurope.com/us/rail/fares_schedules/index.htm
http://www.bahn.de/p/view/international/englisch/international_guests.shtml (the German site)
http://www.voyages-sncf.com/dynamic/_SvHomePage?_DLG=SvHomePage&_CMD=cmdHomepageUK&WB= HP&rfrr=4685ac17fd2e7656e4918c53b246a3f7 (The French site.)

But there are also sites that are set-up in a different way.
This one might be able to help you:
http://www.seat61.com/
http://www.seat61.com/Slovenia.htm

PS,
Tomas Cook was good, back before internet, but now you are much better of with a good rail planner site.
The sites are better up to date, if there are 'printing' mistakes they will be corrected. And if the timetables change mid year, the sites will have it covered.
Plus, they are more precise than the Cook timetable has ever been.