assembler and linker stuff...question

Ive been messing around with some code I found for a compiler recently, and I got it to compile to make the compiler. So what it does now is spit out a .asm file from your code (PASCAL)...but im wanting to make it able to make .exes. So what I _think_ I need is an assembler to assemble the .asm file the compiler spit out and then a linker to make the actual exe. But, im not exactly sure, so could someone either tell me A)what I need to make an exe or B)where I can get an assembler and linker. I have masm, but it wont compile the code...spits out the errors 'fatal error A1000 cannot open file :pasextern.inc (the .asm file I was trying to assemble was called graph.asm)...so any help would be appreciated!

oops, nevermind the missing inc file, I finally found it ;). but anyway, it gives me a ton or errors when compiling: all of them that I can see in the DOS window are: Cannot access label through register segment...so anyone know the problem?

just perhaps your label is trying to be jumped to by code in another segment... maybe using [what might be the equivalent in DOS of another memory module] different options to allow multi-segmented code be released of segmented scope on jumps would help.