[racket] newbie drracket usage questions

Hi,

How would one accomplish the following in DrRacket?

"apropos" (CL/shell) or "lookfor" (Matlab)
Given a search string, return a list of symbols with matching name or 
documentation.
I found that XRepl has the ,apropos command; but I haven't figured out 
an easy way to invoke it in DrRacket.


Finding the source of definitions.
a la ctags or 
http://common-lisp.net/project/slime/doc/html/Finding-definitions.html
Given a function or global parameter, open the file that defined it 
and scroll to the definition.
I found documentation for storing source locations, but nothing on how 
to query the information.


Thanks,
Daniel