about network cards: Actually there is a couple of issues:
- check if kernel find appropriate drivers
- (and if so) check if your tcp/ip stack is set properly..

1) command 'dmesg' output to your console all information about drivers and devices, that kernel found out. You need to check if kernel creates devices 'eth0', 'eth1' (if you have more than 1 netcards) and so on.
Simplest way is

dmesg | grep eth0

you can also type

dmesg |less

and read all that stuff manually

2) If you find 'eth0' device, you must check your tcp/ip stack

ifconfig

prints information about binding ethernet cards to ip . If you get empty output, it means
your tcp/ip stack just isn't set.

Speaking frankly if you are not keen on Linux, better way to setup eth devices and tcp/ip stack is using appropriate 'wizard' from your linux distributive.. Say, YAST for SUSE, Drakconf for Mandrake etc etc. Which exactly distributive do you use?

About C/C++:
gcc - C compiler, g++ - C++ compiler, gdb - debugger, ddd - GUI for gdb, gprof - profiler, gcov - code coverage, and a lot of alternatives for IDE. Some people likes emacs, some people - konqueror (from KDE), some crazy people (like me) - vim. Also you can check CodeForge, Anjuta, motor, eric..