Has anyone wrote anything like this? a block where a member on your site could enter a friends email and it would send them an invite for them to join up. If so could you share please

If you mean send a topic or post from a forum it's allready built in SMF forums.
When you are in a post or topic you have a button that say "send topic"

From there you can add emailadress and the reason you want the person to follow up on the link you just emailed them. 

EDIT! read back again and saw that it wasent what you asked for.
I think i have seen such snippet here or back at SMF forums.
They call the snippet "tell a friend" so do a search for it here or back in SMF.

Thank you very much.

I'll go go search for it

http://www.simplemachines.org/community/index.php?topic=37698.0

That's very cool.  Testing it now. 

Does it work?

Quote from: Xarcell on April 06, 2006, 04:30:43 AM
Does it work?

Didn't work for me.     I entered my name and email address and the recipient's information, which was my own test accounts and I never received anything.

I use this
but you need to have cgi on your host which I think most have, I put it in a article and Iframe, works fine, go to my site below and click on the "recommend us" button in the left block

http://www.lesmonds.co.uk/smf/index.php

Thats pretty cool, think I'll use it, I love CGI.

I am having a little trouble with the csRecommend script.
I downloaded, installed and got the script working. The test script sends an email fine.
I installed a block, but when I click on it, no page pops up, nor does it take me to a page.
I went to Lesmonds Place, and the same results, click on the button and nothing to fill out.
Does the html of the site require a "call" to javascript?
Mine is in text, when I try to open in a new window I get the following;
In the address bar: javascript:ShowRecommend();
and a "Page Cannot Be Displayed error.