how old is Ollie again?
Personally I'd get a mini A-frame or dog walk. Just something to practice contacts on but I suppose you can do this on your contact trainer.
I agree with nic101- tyre
Ever so easy to make.
I found some really good links for homemade agility kit a while back.
I'll see if I can find it again.
Jumps- you can make yourself or you can get some from jump4joy. I always picK these up when we are competitions- they're not too pricey either only £15
each I think.
In the meantime while I look up the other links. Here's a useful site- it's got a "recipe" for homemade PVC jumps:
Agility Equipment
more homemade equipment ideas:
Dog Agility Equipment Index