You're stuck. You're going to want a better and better camera. Just go with an entry level DSLR. Even the most basic of DSLRs is powerful... but if you spend less than $400 (I haven't looked into pricing) you will eventually. Just get a basic DSLR and a basic 28-70mm f/3.5-5.6 lens. You don't need to buy the stuff new, but you'll regret it if you don't.
True, but...You don't have interchangeable lenses, so if I ever wanted to step it up a notch, I'd have to buy a DSLR, so that kind of was a waste to buy a Powershot...I don't know, I'm still doing research honestly. xD