Anyone can help to fond manual for this laptop - dell t3500 ?

Use Google...
I did it for you User manual for Dell T3500 - a user manual, servicing manual, settings and specifications ofDell T3500 - User manuals and advice for your devices - User-Manual.info (http://www.user-manual.info/496443/personal-computer/dell/t3500/)

Ohh what a fast response. :) Thank you very much. This is what I need.

Here is another one.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CB0QFjAAahUKEwjuiP3mjYbIAhWT8IAKHWCtD1g&url=http%3A%2F%2Fwww.dell.com%2Fsupport%2Fhome%2Fu s%2Fen%2F19%2Fproduct-support%2Fproduct%2Fprecision-t3500%2Fmanuals&usg=AFQjCNFYSolW-0o9ch52-L73SpH-x1A_3Q&sig2=UY_psmdLJFIiXVF9BeCivw&bvm=bv.103073922,d.eXY