The 4 operations are covered in the Bond books, but I dont know exactly which age group has them.
If you want to brush up you maths skills (I also had to do it for some areas), you can have a look at the BBC website:
Fractions, percentages and proportions are an important part of the 11+ curriculum, so is problem solving. They will do this at school, but the 11+ problems are harder and trickier.
Just a warning: If your board is NFER (is it?), be careful with the Bond papers. You can use them for Maths, but as Patricia mentioned, not for VB because the question types are different. (or you can use them in early years as an introduction).
Closer to the exam, you may want to pactice Maths with the IPS papers which are very similar to the NFER tests, just a little bit harder.
Sorry about the delay in answering. I don't go near computers near as much during school holidays than when I am working.
Any more question, please ask