The most complete repository of bassoon fingerings is here:
In particular, click on “Fingerings by note name (index).”
While it’s a little tricky to read, find the note you need from the list above the staff displaying the range that includes your note. Many fingerings suggested by a considerable variety of bassoonists, teachers, and professionals are given. Just try them out to find the fingering that works the best for you. Of course, I wouldn’t follow this procedure for every note, just those that are causing trouble (usually depends on context).
If you would like a good basic fingering chart, try this one:
The fingering chart starts on page 14.