If you're looking for problems beyond the usual homework problems, please find below some suggestions. None of the problems described below are required, and none of them are for credit.
First, I have collected all of my old midterm problems. This is a pdf file, and one nice thing about it is that the problems are organized by topic. So each time you finish a topic video, you can work the old midterm problems that only require material from that topic and earlier topics. Also, in the pdf file, an answer is given for each problem. Finally, in the file, each problem has a note that tells on which exam it appeared. So, if you want to, by going into the archive (in the right hand column of the main course website), you can find the midterm (with solutions) where the problem was given and look at a (handwritten) solution -- more than just the answer.
I also have a problem bank filled with problems to be used for lecture quizzes. These are also organized by topic.
In the right hand column of the main course website, you'll find the "ARCHIVE". You can pick a semester, and then look at the midterms and quizzes that were given that semester.
I have collected homework problems from earlier semesters. These are quite similar to the assigned homework, which is called NEW Homework. To see OLD Homework, click here. To see OLD2 Homework, click here.
Next, we have some optional problems via Khan Academy software. Those problems also organized by topic.
Starting in the middle of the semester, we make additional problems available on the optional problems WeBWorK website.
To see suggested problems from the Stewart text, click here. I have organized them by topic.
To see suggested problems from the Whitman text, click here. I have organized them by topic.
Another good source of optional problems was suggested by Abraham Hjelle, and is described at the Student Site in the section under his name and "Material: Optional extra problems".
Vic Reiner's 1271 page has a section, near the bottom, labeled "Further sources of practice problems" that may be useful to you.
Keep in mind that, nowadays, you can find lots of calculus problems with web searches. For example, a google search of "related rates calculus problems" gives many, many hits.