How do I renew my license plate sticker in TX if I dont have a renewal form?

My license plate sticker is currently expired by several months and I have been ticketed. I need to know how I can get my sticker up to date and legal (I know I will have to pay a penalty). Google is absolutely no help... kept redirecting me to either driver's license renewal or registration renewal. My court date is next week... I just need to know where to go or who to call and what I need... Courthouse, DPS, whatever. I think whatever forms were supposed to come in the mail were lost during a change of address. Any help would be GREATLY appreciated.