How to update a rooted inspire?

question is in the title, i did not know that you should not do OTA updates on a rooted phone, so how do i update the phone now that i am rooted?

BAM!!!

Xda is a good starting place.

Sent from my HTC Thunderbolt

Sorry to be a dense, how do I know what ROM I have? 

I used Unrevoked to root my Thunderbolt, I really didn't know what I was doing, but I did follow the instructions carefully, at the end of which the phone was rooted, I was able to use WiFi tethering.  I assume this process ended with some sort of ROM all of you are talking about.  Since Unrevoked seems quite popular perhaps you would know what kind of ROM I probably have in my Thunderbolt now, and where I need to go to get the new updated ROM.  I am also hoping there will be instructions showing how to apply this new updated ROM.

BTW, I did receive a firmware update alert in my Thunderbolt, but I thought that was coming from HTC and since I have been warned that I must not accept OTA updates, and I thought this message must be OTA from HTC, I ignored it.  Is it possible this message was actually from the ROM that Unrevoked put in my phone?

I don't know what xda is, but willing to learn if there is an FAQ on it, or a knowledgebase article.

Sorry for asking way too many dumb questions, but I am willing to learn if you would point me in the right direction.

Thanks a million ....

Just to clarify, since I apparently did not install a ROM after rooting, is my only option to get updated is to do what you say is not recommended, i.e. unroot, take OTA, then root agaon?  Can I not just apply a ROM now on my stock ROM?

I will go through the stickied FAQ section also.  Thank you.

Edit:

Thanks, will start reading 

First, I must say I have a learned a lot from the information here, thank you very much.

However, I am still having a little bit of a problem.

First I tried Baked Snack 1.9, but after download I got an error message, I tried twice.

Then, I tried CyanogenMod ROM and was successful.  I was pretty sure I checked the optional Google Apps, but now I wonder whether I really did, because the Market App was not there.  Also, I could not figure out how to, or even whether I could, restore all the Apps I had backed up using Titanium before I started all this.  Since Market was not there, I could not get Titanium anyway.

So, I have gone back to my stock now.

I think I am almost there, at least I am able to understand some of the terminologies.  Just a little hand holding, and I promise I won't be a pest any more.

Is there a ROM that will let me restore my Google settings and all the apps I have now backed up using Titanaium? 

Thank you....

Myn's is a good place to start. There is lots you can do with it. Cm is a little hard core for a first rom if you don't familiarize yourself with it.
Really you have already taken the leap of flashing a rom. Updating to the latest radios etc. will be no biggie for you. Enjoy Myn's for a few days and then you can update to the latest versions.
Enjoy.