Ok the story is have been digging this girl and kinda have well fecked up every time when I should have asked her out or hooked up with her threw being afraid to make the move.
This happens alot with me and its really beggining to annoy me.
The thing with this girl is Ive just finished a course with her so would never see her again so "This may not be a big step for ye but me it was agonising" I texted her
"Ive put this of for stupid reasons, but would you like to get drinks just the two of us"
She hasnt replied so should I just leave it at that

You have one-Itis. Go fuck/meet 10 other women. Trust me

This or you wouldn't be posting about this and from what I understand you probably didn't build up attraction enough before asking her out.

To the people that have replied so far: You have no way of knowing he has one-itis based on his post, and fucking 10 girls isn't going to help him get this one.

OP: What's your history with her? Have you talked to her before? Have you texted her much before? And just for future reference, the wording of the way you ask her out should be far different.

Here's your text:

"Ive put this of for stupid reasons, but would you like to get drinks just the two of us"

The first part ("I've put this off for stupid reasons") says that you are afraid of her, and you're also making excuses for yourself. Including "just the two of us" is really bad also. It's already implied that it'll just be the two of you, but you intentionally fortified the fact that it's a date. You didn't specify a time/place either. Lastly, it's often best to not form a question, but a statement.

Here's what it could have been:

"Let's get drinks at The Sultry Lizard at around 8."

Simple and straightforward - perfect. Of course, that doesn't mean she would have replied regardless. You need to make her trust you a little and build comfort first.

If she didn't reply, there's not much you can do now. Just take heart in knowing that you learned something from this.

Well shes been in my class since October and well it was pretty much a cert for us to get together on the weekend, but I pretty much messed it up.
Its was obvious she was into me and vice versa
Texted her on and off nothing huge, around ten texts
One-itis possibly a little, I come from a town of 1000 people with no night life and the course that I was doing was 50 miles away from home so its really not often I meet girls I like.

Tell me about it as soon as I sent the text I was like wtf have I just sent, but as sad as this sounds it was the first time Ive asked a girl out

But this isnt the first time this has happened, when I lived in Australia for a year any girl I actually liked I could never ask out, but if I didnt like them and they were just hot I could with my eyes closed

No problems mate. Next time if you ask a girl out and you actually see them on a regular basis it's better to do it in person not over the phone / facebook / whatever. Just to avoid any awkwardness when you two see each other in person.
Reason she didn't reply I think because your text really shows a lack of confidence. But this is fine that's why you are here.
Snarg's advice is good though.