Hi New to site and also Guinea Pig ownership =]

Hi guys, just signed up and have enjoyed reading some threads. Thought i may post in this 1st as its the most relavent. Me and the missus have just bought 2 guineas and we are 'guinea newbies', we have been given (a rather small) cage. As the guineas are only 6weeks old i thing the cage will be ok for the time being but need some advice what to build a new bigger, multi storyed cage from. Im from England, on the south coast. Any advice would be great and much appreciated. Also i have noticed 1 of the guineas sneezeing alot round the hay we use, maybe shes alergic and should change the hay? again any advice on anything would be much appreciated as we are 'newbies' <br>Thanx again.<br> James&Hannah