debugging and other questions

Hi All, I usually debug printing and breaking but I realized that this
method is not very effective for big applications. Many times I tried the
stepper facility but always I abandoned it because it doesn't have a 1:1
correspondence with the source code. I read that in 7.0 the stepper should
be used only on compiled code but even in that case it goes into too many
steps. So, does someone know if there is a way, in Lisp, to have
breakpoint and stepping facilities like many other debuggers have (for
other languages)?

Not related to the previous topic, I have the following question: I have a
big application not written by me that I have to debug. It has a debugging
facility that can print information but I spend lots of time finding out
in which source file is the print instruction that printed a particular
debugging information. Is there some way to print file name and line
number or byte offset from the beginning of the source file or at least
function name (if the instruction is enclosed in a function)? I'm thinking
to some construct evaluated at compile time that adds these information to
the printing lines. Do I have to write this facility from scratch or is
there already something available?

Thanks a lot, Fabrizio.