We are trying to take our car to Sweden from Southern UK this August and it looks as if the ferry prices are higher than we expected (£500+). Can anyone suggest an alternative? I was thinking about a car train from Belgium to Copenhagen, but I am not sure how to search for this. I think German railways may offer this sort of thing. Any suggestions appreciated thanks!

I'm afraid that all the car trains run north-south.
Wikipedia says that the last car train in Belgium departed 2003.

It looks like the ferry from Harwich to Esbjerg is your only choice. http://www.seat61.com/Motorail.htm

A long drive is the other alternative - ferry to the Netherlands then drive via Germany and Denmark. Given the price of fuel and the need for an overnight stop or two you need to do some sums and work out which would be cheaper. I suspect the ferry.

Must you take your own car? Unless it is for an extended stay or you are moving there, it would be cheaper to go as a foot passenger (or fly) and hire a car to tour around.