How do you change female hair to male, I can't workout how and I've tried just moving the information into the other but he just comes up bald. Can anyone help me please?

Unless you're working with children or toddlers, you'll have to convert the mesh if you want your guys to wear it. Male and female heads for teens, adults, and elders are slightly different shapes. You could change the gender number in SimPE, but your hair won't fit nicely to the Sim's head.

How do you change the number's in SimPE and what ones? -is obviously new at this- xD

Try this tutorial. It's for clothing, but I think hair works the same way when you're dealing with genders.

Thank you for all you help, I've converted the hair file now but it does need a little bit of tweeking like you said before. =D

You'll still need to make a new mesh. If you tweak the existing mesh to work for men, it won't work for women anymore. If you want it only for men, that will be fine, but if you want it for men and women, you need two meshes, one for men, one for women. Also, most ages need their own mesh. Toddler, child, teenager, adult/elder, each needs its own mesh.

Do you have tiggerypum's example bodies and faces? The heads are very useful for making hair meshes fit properly.

Most of the time it is just best to start with the correct age and gender. That way you get the hair group correct. You can just resize and toss the other hair_03 etc groups on top of the correct head shape.

My article has everything you need to know to make your first hair mesh package.