Hello Spotlight & welcome to the forums :)
I can't tell you easily in one forum post how to use Logic Express 9... but I can give you a few tips to help you get started and direct to resources that will help too.
1. Connect all your hardware to your Mac.
2. Open Logic Express.
3. Create an empty project.
4. From the new tracks dialogue choose a mono audio track.
5. Set the input of the track to the same input on your audio interface which the mic is plugged into.
6. Go to Logic Express > Preferences > Audio and check that the device is set to your m-audio interface.
7. In Logic's Arrange area click on the little R button to "record ready" it.
8. Now click on the Record button in the transport to begin recording.
For some free videos designed for users switching from GB to Logic check out:
The Core Logic 101 is also a great place to start to learn how to use Logic Express or Pro 9:
Finally, I'd like to add that how you set up your microphone (using a pop shield), the room you record in, using closed headphones and distance from the mic will depend on the type of music you are recording. e.g. a classical singer may position a microphone far away, while most other singers will be about a foot away depending on the desired effect.
Then adding effects will make a difference to the recorded vocal sound, but it's now as easy as saying effect X will give a better quality of vocals. However, some effects that may be of interest are the compressor, Channel EQ, Stereo delay and reverb.
Hope that helps