Welcome to the forums!
It sounds like you have only broken the screen, however I cannot be sure. It could have done more damage than you think!
Usually your insurance should cover accidental damage - I'd definitely check with them first. It would usually be based on you paying the excess (not sure what that would be though) - could be worth it for peace of mind, as I'd imagine they'd get it done by HTC.
If the insurance won't cover it, you may want to check with HTC to see if they can repair it for you - I believe that usually they would require you to send it in to them and then they'd have a look, let you know how much it costs and then, once you ok it, do the work. Worth noting that any work carried out by them would be covered by a warrantee.
The third option would be to take it to a mobile repair shop on the street, who would probably look at it and then work a price out with you - I would recommend asking them for a quote before you get the work done, so that you don't get stung for a bill that's higher than you thought. This would not usually be covered by the manufacturers warrantee.
The final option is to do the work yourself. I have seen several people on here talking about buying the parts on the internet (eBay, I think... be careful where you buy from though, checking other buyers reviews of the seller - you wouldn't want to end up with non-functioning parts/the wrong parts. I know there are lots of "how to" videos on YouTube and it is possible, dependent on your electronics proficiency to do the work yourself... I'd be careful, unless you know what you're doing. Again - you would not be covered by a warrantee.
Sorry if I've only told you what you already knew but, ultimately, it is your decision. If you want to go down the route of doing it yourself, I am happy to try and find some links for you.
Let us know if your insurance will cover it and, if not, how you want to go from here!
Cheers,
Rob
EDIT - sorry... didn't realise how long this was until I posted it!! 
