Three things which may be useful to you :
1. You can install OS X on an ordinary P.C. It's worth it! It's called the osx86 project. However it is piracy, and it does make you want to buy a mac, so watch out!
2. You can save money through an educational discount if you or your girlfriend are students. For example at the tuks zastore (tuks.zastore.co.za), I get 10% discount which means a basic macbook is like R9700.
3. Look around for second hand macs, at
www.c3.co.za and the MyAdsl classifieds. At c3 classifieds, I just saw a black macbook (usually 13 grand) going for R9000.
Enjoy your Apple Computer!