2005 manual won't go into gear
 

I am looking at purchasing a 2005 TL with the following problems:

Car was runs fine, clutch needs to be changed. Car won’t go in gear when the vehicle is on the ground. On a jack it goes in gear but clutch will not disengage.

Any ideas?

Simple (LOL) clutch change, possible linkage, or transmission problem?

Has 190k miles on it.

Did you check the level of the clutch fluid reservoir? Probably the clutch master or slave cylinder would be my guess but with those miles might as well do a new clutch/flywheel also

A failing clutch would be slippage or hard pedal. A non engagement senario means you need to look at your hydraulic system and possibly the clutch pedal bracket mount.
Start with fluid level, then see the slave cylinder fork if it's making full extension.

My guess is the pressure plate self adjusting mechanism failed and worked its way the whole way out causing the clutch to be permanently engaged. My old Audi S4 had the same type of LUK clutch pressure plate and this happened to me. I don't think it's super common, but it can happen.