CS department web pages for specific schools you are interested in may list job openings
Sending in an application
Sooner is better. If you send it in late December / January it is already getting late for the next school year. Target sending applications in October or November. Different schools have different deadlines -- make sure you meet the deadline of any school that you are applying to. Note: make sure that you send in all of the application materials for each school you apply to. Different schools have slightly different requirements. Missing an item from your application means that the faculty from that school will likely not even read your CV, as your application will be held up in the administrative offices until it contains all of the required material.
Preparing for an interview
Identify influential members of the faculty who you will talk with and prepare a brief summary of their interests. If your interests are similar, make sure you have read some of their papers.
Prepare a list of courses that you are interested in teaching. Also, prepare to explain how you plan on teaching different classes: techniques, content areas, etc. This will be somewhat similar to your teaching statement, but be prepared to go into more detail.
Prepare a list of topics that you are interested in, and try to see which faculty would have similar interests. This includes academic subjects as well as extra-curricular activities.
Post-interview suggestions