I was once asked in a job interview what my favorite method of sound effects creation was i.e., did I enjoy tweaking canned sounds from libraries, or did I like creating sound effects from scratch. Although I prefer creating sound effects, sometimes it's just more appropriate (cheaper/faster) to use canned audio.
Here are some sound effects I have created using a variety of sources and processing techniques. Please bear in mind that these files are compressed, so stereo imaging and high frequencies have suffered as a result.