Hi! - welcome!

well, the best investments with a limited budget would be the free software and there are many tutorials to help you through. GIMP springs to mind, but there are others, some made by other memebers here - like Wilbur, which I find particualrly useful. Then theres also a free The Roleplying City Map Generator

check over at the How to section for more details and there's also a software disccusion thread and list of software here


you'll find there are plenty of helpful folks here.

cheers

jez