I'm in the U.S.; Don't know about non-universities, but most research institutes using federal funded grants for post-doc programs seem to pay per the NIH guidelines:
Postdoctoral Years of Experience:
0 $36,996
1 $38,976
2 $41,796
3 $43,428
4 $45,048
5 $46,992
6 $48,852
7 or more $51,036
http://grants.nih.gov/grants/guide/notice-files/NOT-OD-07-057.html
They can be supplemented from other funds to make a more liveable/competetive salary. These stipends are terrible, amounting to a paycut even at the 7+ year experience slot compared to what I am currently making as a research associate with an graduate degree and a lot of experience. Another route is 'Staff Scientist" which usually gives a better salary, but may not have all of the mentoring/protected time for getting your own funds as a post-doc, depending on who you work for.