I have a 3 year old Border Collie who gets very scared whenever anyone visits the house to the extent that she won't come into the room that they are in and sometimes even the room next to that. We allow her an escape route so she can be on her own otherwise she backs into a corner and barks or runs round looking for a way out. We'd love to get her some form of training to help her to be more comfortable when people come round but most training seems to be obedience which we don't need or Jan Fennell type dog whispering which I'm not sure about.

Can anyone please suggest any books/types of training that I could look at to help her getting so stressed out?

Your best bet would be a good behaviourist using just kind, non-forceful methods. I'm dealing with a dog of mine not dissimilar to this, and with him its a question of it all being his own choices. Never any force. It would for instance help a lot if you could enlist visitors (maybe invite people who were willing to help) to help him gain his confidence. This would have to be done very slowly, and involve lots of food rewards, starting with you rewarding him for just being in the same room as other people, then visitors just dropping food on the floor far away from them at a distance the dog will feel comfortable enough to reach to take the food, then gradually get him closer until eventually he will take food from the floor next to a person and over a period of time in the end from their hands. I.e. he needs to learn to associate visitors arriving with pleasant experiences. Clicker training is ideal because you can easily mark even a tiny step forward. I can't stress enough though that it has to be done SLOWLY and won't happen in a day, rather weeks or months, and ideally you should have the help of somebody used to dealing with nervous dogs.

i have the same problem with my TT, she has always been nervous. i make a point of telling people not to look at her when they come in or speak to her and after they have been in the house for a while she will begin to go and sniff them but this only works if they do as you say. at this point they can drop the treats on  the floor as she sees them as no threat.
it is very hard as most people can't stop themselves giving a dog attention whether it wants it or not and my TT is very cute so people find it hard to resist trying to stoke her.
i have been working on this for five months now and she is very slowly getting a bit better but as said before you can't force things. i go to training classing not so much for the training but so she meets lots of people in a nice enviroment and because they concentrate on their dogs she comes out of herself and actually tries to get their attention.

Thanks guys, I'll give these suggestions a go and hopefully we'll get her sorted.

For some help try reading "Cautious Canine" by Patricia McConnell and "Help for your Fearful Dog", Nicole Wilde.  I've found them very useful.

Lots of patience needed :-)

I rescued a Collie aged approx 8 months, this was nearly 11 yrs ago, she was the most nervous thing I'd ever encountered, not just with visitors to the house but also out walking and anybody that came within 'miles' of us. She would drop to the ground and her bladder and bowel would 'go'.

As MarianneB says it has to be slow, steady and gentle.

We always allowed escape routes, never forced anything with her, when visitors came to the house they were pre-warned to ignore the dog, be quiet and calm, we got them to casually hang their hands off the arm of sofas with pieces of stinking cheese and not to pass comment or make noise when she crawled out of the corner to quietly pinch the cheese.

If she saw our other dog being petted and crawled forward for attention they were to say nothing and act as though she was not there. I know that sounds mean.

It took several months of being calm and almost ignoring her until she felt ready to 'join' us and ask to be petted. Now we have the most intelligent Collie in the world and she is the leader of my now pack of 6 dogs

Bought a tear to my eye that explaination, as a BC owner thank goodness you rescued her.

I'm glad we did too, we learnt a lot about dogs and how to manage them from her.
At 11yrs she's still an active little moo and although very small for a BC she has huge courage and character, she can be a wanderer and will still dig for worms and eat them like she would have had to do when she and her sister were abandoned all those years ago as 5 month pups in Wales.

Hello!
(Welcome to Champdogs :) )

I would also echo Marianne's wise advice have a look here -> The Association of Pet Behaviour Counsellors

Gwen Bailley has a great site I have a copy of her book 'Rescue dog'.

I'm not a fan of the Jan Fennell ilk I have to say ;)
For some good back ground reading Clicker Solutions Articles are good to cherry pick info on Positive Training methods.

Wishing you the very best of luck, keep us posted on how your all getting on wont you?
Best wishes and hope this helps :)