If you are going into wall studs through plaster/drywall then you want to use 3" to 4" lag bolts available from your local hardware store. If you order a mount from Monoprice, then that mount will come with lag bolts in the bag, and those should be used.
Hit the studs.
Which TV are you hanging?
You should not be using liquid nails, or anything else in this process, unless it was already used on the plaster and wood studs. Four lag bolts hitting studs will support 300+ pounds of weight without any issue at all. Make sure to use the washers which come with the mount as well.
Generally, an ideal setup, is that the mount will hit two studs that are 18" apart from each other and that the center of the mount is then the center of the TV location.
Which TV model do you own? Plasma? LCD? Size? Weight? If you have a LED lit LCD (Samung) then they are incredibly light and could probably be supported by velcro (don't do this!).
Larger sized displays, like 60"+ can use the 'oversized' mount from Monoprice which can easily handle displays that size and can potentially hit 3 studs in the wall. It offers a lot of lateral left/right motion with that mount which is great for placement flexibility with offset studs and a standard VESA mounting pattern.