The stock thermostat will turn off the heat or A/C when it gets to the set temperature, you don't need a programable thermostat to do that. A programable would allow you to set a schedule to where when you wake up, it's one temperature, going to be it's another, etc.
As far as not allowing the blower to run all day, it shouldn't do that even with the stock thermostat otherwise you have another problem. Does your unit not shut off?
As for a programmable one to purchase not a huge help, I know without being model specific but, almost any programmable thermostat will work. There are some in here if you do a quick search where they will give you details on how to connect it and list the models. Alot of people go with a Hunter thermostat.
I personally switched out my duo-therm thermostat for a Hunter programmable thermostat which I got at Walmart. The only problem is, you can only wire up the high speed fan or the low speed fan unless you add in a micro-switch. So when the blower kicks on, it comes on at a high speed. You can also wire it so it's the low speed when it kicks on.
2012 Keystone Sprinter
Still sticking around for the good people and advice.