The end cap on the right side of the dash has four spring clips that hold the piece on. I have replaced the passenger compartment air filter three times now (2010) and find the process relatively easy although my 67 year old frame disagrees.
You DO want to be careful when trying to remove that end cap. Using your finger nails will probably only end up with broken finger nails. Using a flat bladed screw driver has a tendency to make a permanent dent in the dash face against which it is pried.
I have found that using a small pry bar meant for baseboard moldings works very well to get it started.
After that it is only a matter of removing seven screws and tugging hard on the glove box assembly to get it to come down (again there are two of those spring clips).
The door over the filter itself is held shut by three plastic clips on the top and sides. I find that using a small flat bladed screw driver inserted through the U-shaped clip allows for the clip release relatively easily.
I order the AC/Delco filter from Amazon.com but the first one came from a company named Tye. They included an instruction sheet with grainy pictures the highlighted the locations of attachments that needed to be removed.
If you do not normally work on your own vehicles, then you probably do not want to tackle this one.