CLEP Humanities

[TexasTink]

2 part question - first, do y'all know what practice tests are most similar to the real test?  I took the Free CLEP Prep cold to get an idea of where I was at - scored 61%.  I also was able to pinpoint 3 main areas to work on which was great.  I went through the Modern States course - unfortunately, they copied all the questions from the Clep Guide so I can't use that sample to get an idea of where I am anymore.  I do feel like I'm fairly comfortable with their questions though.  I bought the Peterson's tests and took the first one and got a 45%.  It was terrible.  I hadn't even heard of about half of the material.  But it also seemed far more detailed than the previous two and was majorly focused on the 19-20th centuries.  Which ones would be more in line with the actual test/subject material?  Is there any other test I can take to measure how close I am to being able to take the real test?

Are there other good, comprehensive study materials out there?  Is Instantcert good for this test?