I looked up a '91 Honda Accord DX here:
http://www.crutchfield.com/whatfits/...utchfield.com/
Most likely, the speaker sizes are the same among the different models. In the above model, it was 6 1/2" all the way around (4 speakers).
I use Crutchfield for
information purposes only. Their prices are far too high.
www.ikesound.com (scala1 on Ebay) has
excellent service and usually VERY good prices. I fried my own car amp some time ago because water got in it. I sent it back saying it quit on my and they replaced it with a new one with no questions asked. The sales people on the phone each time I called were always very helpful.
You will get all different opinions when it comes to audio, since sound quality is mostly subjective (although there are trully crap brands). The best bet - if you can - is to go to an audio store and listen to different models yourself. Two things to keep in mind: what
you want to pay and what
you like.
The speaker that is the most money is not necessarily the best
for you. If you cannot distinguish the difference between a $50 speaker and a $400 speaker, why waste your money?
Now that we have that out of the way, IMO (of course), Infinity and Boston Acoustics are brands that I like for speakers. I will admit, I have never had the opportunity to hear Infinity speakers but do know that the reputation of that company is irrefutable. They make excellent, high build quality products. In addition to owning a pair of BA home speakers, have heard their car lineup and, IMO, they are great. I can't remember any other good brands right now....
I don't like any of Sony's products. At the very least, their car amp and sub designs are some of the worst in existence, probably only beat by Wal-Marts "Roadgear" brand. I would stay away from Sony period....although, maybe others have had 'good luck' with their speakers...
Some other sites:
http://www.audiodiscounters.com http://www.buyloud.com www.caraudioforum.com is a good place for more info. I find that you have to *bump* your thread sometimes because people won't reply. I think that's primarily because there are about 90% newby threads in the General forum

and frankly people get sick of answering the same questions over and over again (I did). In other words:
search ("good speakers" for instance) and if you still can't find the info you are looking for, THEN post a new thread and make sure you say you searched the forum already
Good luck! You can PM me if you want, but most likely I will see this thread again
Warthog