potty training my 3 year old son with ASD or trying to!!

[bananasinpyjamas]

Anyone got any ideas to help motivate my 3 and half year old son who has ASD with potty training.
He uses pull ups during day at mo.. lie down nappies (as he calls them) at night When tried to potty train in conventional way going cold turkey with nappies at first would say wee wee when it was happening, much praise and celebration, but a couple of days later didn't seem bothered. Almost as if he got used to it so it was no longer a problem to him.
Have been trying to think what will motivate him with actually having a wee in the right place be it potty or toilet. Stickers or praise won't be enough. Far to boring and meaningless for him. I'm currently thinking about musical potties. He's very kean on music and sounds and can do the answer phone message off to a t!!
I am slightly concerned about introducing a new thing which he may become completely dependant on but perhaps is worth the risk.
Has anyone had success with these or any other ideas which might be worth a try.

Have you spoken to the childminder and school about toilet training? It's just that they will have to be involved at some point and they may prefer to just dive in at the deep end with you and see what happens. We used pull-ups just to start with for the taxi journey to school because it is a long way and not fair on the driver to have to get ds's seat dry for the return journey if he wet it on the way to school. His teacher would take him to the toilet and change him into pants as soon as he got there. It didn't take long for him to be nappy-free in the taxi as well, once he got into the routine. I went into Tesco and got a big bag of stuff to send into school rather than fiddle about every day (they are happy to put stuff in the washing machine so that was ok). I got 2 pairs school trousers, 10 pairs pants and 5 pairs socks for about £10 so it's worth doing. Actually he's hardly used any of them so maybe I was being a bit on the pessimistic side .

Not sure if this thread has run its course for now and the advice and stories has been brilliant. The potty training is proving kinda difficult and I know its early days. My main problems are getting ds to stay on the potty or toilet. Nothing seems to work so far. Books, promise of chocolate, toys, nothing is interesting enough to stay put. Also doesn't really seem to have any idea whatsoever that wee's go in the potty or toilet and all that. No verbal language at this stage to say has had a way either. Also with no pants one one hand is permanently attached to w#*!!y, with pants and trousers on this doesn't change much.
Feeling a bit dispondant today about the whole thing. If only ds would stay on the potty for even a minute that chance wee may occur so I feel I could at least show and explain with great celebration!!

I couldn't get ds to stay on the potty at first either but we had several of them dotted around the place so at the first sign of anything I could grab him and rush him to one quick! To start with I was mostly too late but at least it gave him some idea of what it was for. Of course that meant him being half naked indoors and yes, hand permanently attached to willy!, but he's doing that a lot less now so I guess the novelty is wearing off!