lifter/cam install

Couple of quick questions. I have noisy lifters above 4500 rpms. Ive been told installing a new set of lifters will cure my ails. I have also heard that if I install the new lifters, I should install a new cam as well. Is this true, or can I simply install new lifters with the stock cam ??? Any hints for the weekend mechanic to make the install quicker/easier? It appears pretty straight forward in the Haynes manual.

Engine is bone stock except for k&n and pulleys.
I have been told by a couple shops that its more than likely my lifters. I hear it first thing when the car starts up, then after its warmed up its pretty quiet until I hit it off an exit ramp, or hit it to pass someone on the hw. Its an auto w/stock gearing at the moment so the rpms are pretty low during city driving, and in that case I rarely hear it unless I hit the gas hard.
Car has 110,000 on it, and the only time it sees high rpms is when I really get on the gas now and then.
Thanks for your help man, and to any others that chime in.

hmmmmm that doesnt sound good either lol. any way to check and make sure thats what it is? would installing a new set of springs take care of that? Im heading to an auto fair this weekend that supposedly has awesome prices for parts. The way its looking, I may need to get a set of valve springs, cam, and lifters