need help looking for a good HT receiver

My father is looking for a very good receiver for his home theater. He wants something that can use an ipod docking station

He has an Onkyo TX-SR603 right now but it took a crap on him and blew out all the tweets so he just wants to get another amp instead of having it fixed.

I know nothing about HT so I really need your help.

This is what he wants:

1. of course a 5.1 or 7.1 it doesn't have to be THX certified.

2. He wants to be able to put an ipod to it (via docking station)

3. 80-100 watts per channel

4. he also has an amp so he wants to be able to connect that amp to the receiver.

5. budget around $350-$600

As far as I know he's just using regular speaker connections (pos and neg) and RCA connections for the speakers and i don't think he's using XLR connections.

I'm just throwing models out there but what about the Onkyo TX-SR605? can another amp be connected into this receiver?

It's supposed to be a good receiver, very highly rated. but again, i really don't know. ****, i got to learn about HT. I hate not knowing a thing about this.lol