I have been in a situation before where I was essentially thrown into a job position with no training whatsoever. It was very much a "sink or swim" environment where I was expected to become productive and figure out my place basically on my own. This was a very, very large company (Fortune 50) with lots of employees, tasks, and highly-matrixed teams; the simple fact was that most people didn't have a lot of time to spend to walk me through some of the basics that everyone there took for granted.
The result of this was that I spent an hour trying to figure something out that one of my coworkers or bosses would have been able to explain to me in five minutes or less.
Is there a way to handle this without being a nuisance to your team (i.e., constantly asking for help and explanations) while still being effective and adding value to your assignments?