Make small talk. Thats always quite good at getting people to open up - start with a " hi, how are you?" every day, ask about their evening or weekend. Doing this can allow you to find out more about them and their interests. Ask about their holidays, and even if you wont be going, ask if there's somewhere they'd recommend in x. What skiing is like or the best resort is. Even just about the work you're doing can help - if you need help for example, or if there's anything you can do to help. Whilst this may be difficult, doing it little and often can make people start to notice your attempts to interact more and can encourage you to be more confident. You don't necessarily need to invite the whole team out for a meal, but even inviting a coworker (especially one who you've more frequently talked to ) out for drinks gives the impression that you are still able to socialise.
As a shy person myself, i found it really difficult starting work. I work in a posh area, and many of my colleagues either go to fancy, private institutions or drive big SUVs. But, having been there a year I'm able to talk to all them (except the big boss) about a range of things.
Don't try and spend all your money trying to fit in, but at least trying to relate to them may be helpful.
Hope this helps (: