There are a couple of websites out there who's aim is to give people information on most of the board games out there, which will include their rules and instructions.
This website contains all of the information that you could ever need to know about any board game, including Blurt.
As well as instructions on how to play the game, it also provides information on where to buy it, different versions of the game, and forums that have a discussion currently going on about it.
This site is similar but doesn't go into quite as much detail as board game geek. It only provides a small amount of information on the game and a comment section that allows people to share their experiences with it.
However it might be worth using this site as it provided the 'official blurt game rules'.
This is a copy of the official rules of blurt, the same as the rules given to you with the game. It gives you all you need to know about how to play, such as; how you play when taking on different roles in the game, how you win, how to play in team and more.
These instructions also provide you with rule variations, so you will be able to play the game many times before you get bored.