Now, as to what to do.
If there's a local garage you trust, run it into them. Just get them to look at the rear end.
If there isn't, take it into KwikFit, ask them to balance the fronts, but mention the other handling issues. Chances are they'll take a look at it for free, which will give you some idea of what's up.
It could be that there's someone here who could swing by and take a peek, too.
Next step, if you're prepared to get your hands dirty, is to get a Haynes manual (Halfords usually have them in) and borrow some tools.
None of the jobs suggested so far are beyond the amateur.