I would avoid shrinking if possible. It will cause fragmentation issues with any indexes you have and thus performance issues. It can also cause fragmentation in the file system.
If your in a crunch, add a second datafile in the same filegroup to a different volume. SQL Server will start putting new data in that new file. It will do this until the files are of equal size and then basically round robin going forward.
This should allow you to focus on averting a full drive until you can get a bigger disk.
