I have a sony vaio laptop, couple years old but not super old. Yesterday I couldn't get the computer to even register the ac adapter, no power lights, battery lights etc. Played around with it a bit today (needed to know whether it was the DC inlet that was the problem, tested it and was getting 19.9 volts out of it so it's working) finally the computer attempted to boot up, power light came on and battery light flashed, fan turned on, cd attempted to boot up to then nothing..nothing at all registered on the screen. Tried it again and suddenly the power light, and both battery lights are on but it's not doing anything, not even booting up and I can't hold the power key to turn it off. So now I have no idea what to do. The only way to shut the computer fully off is to remove the battery but I would like it to atleast attempt to turn on. The lady at the computer store didn't give me much except it could be a motherboard, hard-drive, faulty connector...Does anyone have any ideas that I can atleast test out before I spend money to get this thing looked at?

Hold down the power button for 5 seconds to turn it off

Also have a look here: Tutorial: No POST (Power On Self Test)

Please give us model number and configuration.
Some of those Sony models have screen inverter problems, while others have hard drives that fail early. While still others have air channels to and from the cpu fan that plug up with lint and dust.
But first thin to do, methinks, is to run the 8-Step program that so many on TechSpot find remarkably useful: Do the TechSpot 8 steps: http://www.techspot.com/vb/topic58138.html I no longer remember whether this is the most recent version of the tool set, so you might want to take a look around.

I keep finding things on google about a reset button but I have absolutely no idea where i would locate that?!?! It's worth a shot I figure but if someone could direct me as to where I can find it that would be great. I would also like to try removing the battery from the motherboard, but again don't know where/or how to access that?!

Sony motherboards are difficult to access, and if not experienced in getting inside the case, you can damage parts that cannot be replaced. The plastics become brittle and crack or shatter.

Usually the reset is a button that can be held down for 30 or 40 seconds... First, the start button, then the F1, F2, F10, F11, or F12. It varies from model to model and Sony is no help.
Many sony laptops can be opened after removing the keyboard, which can be done by removing six or eight screws from the bottom, then moving some sliders hidden between keys in the keyboard. Again Sony is no help because they rarely publish the schematics.

But as requested before, we cannot give you much help unless we can have the model number, configuration, and age.

The model number is PCG-GRZ660 on the top of the keyboard, to flip it over and look at the tag on the bottom it's PCG-8L1L? The configuration is Windows XP (I think that's what you are looking for?)

I got the keyboard off and still couldn't see anything that looks like a motherboard battery (I'm told it looks like a watch battery) or a reset button?!

No. Laptop batteries usually do not look like watch batteries or thick quarters... they usually have wires, and the wires can be as long as 9 inches... or as short as 1.5 inches... and can be in all sorts of strange places.... and it is difficult to say what they will look like....
Go to eBay, and run a search for Sony CMOS battery... and you will see several types for different models of Sony laptops.

Based on the pictures I searched it looks like it was right in the top part all along, removed it, put it back still nothing...Didn't see a reset button anywhere near it though?

No that reset jumper, is usually only on PCs ie not laptops

Was reading that to determine if it's the harddrive remove it and try to boot it up, did that, LED lights came on and then off, put it back in tried to reboot, got nothing, not even LED lights this time. I checked to make sure I put it back properly and I did...soooo frustrated...
(It's the slid out harddrive so I didn't go deep into taking it apart or anything just removed a screw and pulled it out)

Just disperse all voltage, as per the Tutorial guide I posted way up there at Post#2

afaik, there's ati mobility radeon 9000 installed in this model? anyway, it seems, that your ac adaptor is weak to give normal power supply.first, try to change ac adator, and check the result. also, these models have known issue, connected with memory slots(bad soldering). you can check this, only by using a binocular microscopy.

We tested the ac adapter and the dc inlet inside the computer and both are giving off the correct voltage