Source Insight is an IDE, if Google serves me right.
There are at least 2 IDEs for Linux that I know of. Code::Blocks, which I've used, is actually multiplatform, and I've found it to be excellent, almost (but not quite) up to the standards of Visual C++ and other expensive editors. It's free. Note, it's only for C/C++, and maybe a few other languages (D, I think?).
The other, Eclipse, I have not used. It's often referred to as being a resource hog, from what I hear, but it works with many languages. Again, this is heresay... I have not used it myself.
Many programmers I know use only a text editor, makefiles, and GCC for their work, so it is certainly possible to do so, but if you don't want to, either of those tools should help.
Hope this helps!