I'm glad to hear you are asking for advice before jumping into something. That shows you are ready to do some more checking on your own. Check the link at the bottom for a starter. They have everything you need except the QLogic stuff.
Just about any single DIN receiver should work. Beware advertised power ratings, almost all inexpensive aftermarket receivers put out about 15-20 watts peak power, no matter what the box says. That said, pay attention to other details, like tuner performance, and output tunability. What I mean is, can you adjust frequency turnover settings, sub outputs, how many RCA connections are available for connecting to an amp. A decent head unit will have a set of RCA's for front, rear, and for subs (3 sets total). This way if you want to add amp(s) later, you just hook them up. It's better to spend a little more up front and be able to expand later than to have to start all over again if you didn't get enough points to hook everything up. If you don't have enough RCA's for the front and rear speakers, you can add line-level converters later. Any reputable sound shop can sell you these. Don't hook up the speaker wires directly to the high level inputs on an amp. You will get a lot of distortion that way, and blow speakers.
You should be able to put in a decent quality amp for not too much money. Pay attention to THD ratings (total harmonic distortion). Anything above 1% for your system is not good. The lower the number the better. Also, you will get a richer sound this way. A four channel amp will handle your front and rear speakers. A separate single channel amp will handle a sub if you install one.
Speakers ... you can put in 6 1/2" speakers in the doors, and 6x9 speakers in the rear. Make sure the door speakers are shallow mount type so they don't interfere with things like windows when the are rolled down, and power window motors, or manual roll down knobs. You should be able to get some decent sounding speakers for not too much money. Make sure you listen to what you are going to buy both with and without an amp. It is better to spend a little more on the speakers up front and add an amp later than to buy cheap speakers now and blow them up with an amp later. If you can afford it, QLogic makes replacement kick panels for your car to mount the 6 1/2" speakers in. They will sound WAY better than the door mounted speakers.
A single 12" sub will probably be all you need. A lot of folks will try to sell you on more than this, but if you go that route, all you will hear is bass. You won't hear the rest of the music.
Good luck!