There are lots of plug-ins out there, some of them free, most of them not.
Premiere technically never had an old film look filter. However, what it did have is access to the QuickTime filters. (Premiere Pro lacks this capability.) QuickTime has an old film look built in, which you could apply in Premiere 6.5.
There is a way to use the QT old film look in Premiere Pro, if you still have Premiere 6.5 or if you’ve purchased QuickTime Pro.
1. Create a black matte and put it in the timeline.
2. Make the length of the matte either A) as long as you’ll need it, or B) 30-60 seconds, or some other arbitrary value which you’ll loop as necessary. Beweare that option A gives you a much bigger file.
3. Apply the Transform effect and lower the opacity of the matte to zero. We basically just need a timeline that has nothing in it.
4. Apply the QuickTime Effect and turn on the Special Effects > Film Noise filter. Tweak settings as desired.
5. Export the timeline as an AVI or QT file using a codec that supports alpha channels, such as QT Animation or no compression (huge files!). Set the colors to Millions+ to actually get the transparency.
6. Place the file into Premiere Pro and place it on a track above all of your other clips.
Done. If you have QT Pro, but not Premiere 6.5, follow the instructions above to create the matte and export it as a transparent QT file. Then take it into QT Pro, choose File > Export, and in the options apply the Filter. Make sure your export options remain for Millions+ colors and a codec that supports alpha channel.
Note that this film effect only applies scratches and dust, really. You’ll probably also want to apply some sort of color filtration (sepia toning or over-saturation and color tinting) and maybe some noise to simulate film grain.