Resources I use to check the credibility of unknown journals:
- Thomson ISI
- Web of Science
Hindawi Publishing Corporation
Founded in Cairo in 1997.
22 of the 300 journals have an impact factor between 0 and higher than 0, but below 2.064 (4.096 according to the Hindawai home page)
Some other researchers impressions: http://list.uvm.edu/cgi-bin/wa?A2=MEDLIB-L;wGArog;20110726180255-0700d