I get the same thing, Walmarts main page. The main thing you need to look at is speaker impedance. Most car audio systems assume that you will be driving 4ohm speakers, conversly, home audio setups generally use 8ohm impedance speakers. This is important because if you try to drive higher impedance speakers with your amp(either built into the radio or external) the amp will run hotter and blow quicker. If you try to drive lower impeadance speakers, you will push more current to the speakers and blow the speakers or amp, or both. Chances are if the radio and speaker come in a set, they have already been matched.

The next thing you will need in order of importance is a wiring kit. You buy them based on the make and year of your vehicle(in this case 94 honda) You then need to buy some butt splices and a crimping tool. (fairly cheap) Use the instructions provided with the radio and the wiring kit to match up the wires by function. (i.e. rear right speaker, +12 switched, +12 constant, etc, etc)

Next, you will need to purchase a mounting kit. Again, this is based on make and model. Your local wally world should have all this stuff. Assemble the mounting kit according to the instructions provided, then mount the radio in it. You can then install the whole thing in your car.

As far as the speakers are concerned, just remove the body panels, or grills that cover them, remove the old speaker, then install the new speaker. (be sure to watch the polarity (+ to +, - to -). You may want to purchase some spade connecters as well. (You can buy spade connecters in a kit along with butt splices) Sometimes, speakers have short lengths of wire with spade plugs on one end and stripped wire on the other, in which case you can just butt splice the orignal wire to the short wire that came with the speaker, and hook it up that way.

Let me know if you need more help, or have questions.

Good luck,
Rendman

p.s. I live in Japan so responses will be delayed.