Don't "overuse" the contact cleaner. (Don't leave a residue, especially enough to cause a short.)
If you're not into DIY good quality, reasonably priced cabling for all your audio needs can be found at Blue Jean Cable, Element Cable, or Signal Cable.
I recommend hanging around here, checking out audiogon.com for used stuff, and searching through ecoustics.com for "professional" equipment reviews to discover what's out there and what to look for.
Find out what kinds of music you like, then listen to it live (the only true gold standard for fidelity). Once you've learned what the "real thing" sounds like and are familiar with available equipment you'll be ready to shop. When shopping, don't try to seriously listen to more than 4 or 5 pieces per visit as the ear gets easily confused and aurial memory fads. Unfortunately most retail outlets are poorly staffed (don't know much), poorly set-up (typically open spaces that aren't homelike even if not competing with the sounds from other systems/listeners), and poorly equipped (mostly HT and stuff aspiring to mid-fi status). Hopefully its better where you live, ask your Dad.
Attending local audiophile meetings is helpful and audio trade shows are a real treat.
