Suspension - told not to contact work how do I get evidence to defend myself.

 I have been suspended from work and been told not to contact any collegues whilst an investigation takes place.

I am concerned that I because I cannot contact work and I have had my laptop taken from me that I will not be able to ask my work colleagues to provide evidence to back me up and I cannot get access to my electronic diary on my laptop to confirm events.

Further have been told that my manager called the team together and told them I had been suspended despite their being an assurance in our discipline policy to confidentiality throughout a suspension period.

Finally I am due to go on holiday with a work colleague (this been booked for months) and he has been told not to contact me or face discipline for disobeying an order!

I am not in the union should I contact a solicitor and can they come into the investigation hearing

Advice on any of the above would be gratefully received.