It's been quite some time since I've delved into anything computer-wise. So bear with me.
I have a laptop hard drive which I'd like to swap out with a larger/ improved one. But, I'd like to clone to current info onto the new drive. I want to know if it is possible to connect the old laptop drive and new drive up to my desktop computer, and then clone the old one onto the new one like that. Instead of buying a transfer caddy/kit. Also I'd appreciate any particular recommendations on free cloning software.
But I would suggest you to fresh/clean install of OS on any new drive. Actually cloning it find of transferring that is not a good way to do things. OS always needs to be installed and not transfer. And cloning it somewhat troublesome if you are doing it first time, if you ran into problem then it will be a headache for you to solve.
And yes you can connect the Lappy's HDD directly to the MB of a desktop as a second HDD to run. No need for a caddy.
I suggest Macrium Reflect (free). I've used it myself to restore drives and swap a netbook HD for an SSD. Reinstalling the OS is probably optimal, but I didn't when I did the netbook swap and I didn't notice any problems.
Also, I think you might need a 2.5 => 3.5 kit to hook the laptop HD up to your desktop. Depends if your case came with one or not.
Oh, and you don't need to have the new HD connected to your desktop to do the clone. When I did the netbook swap, I put the cloned image on an external drive, then ran Macrium off a flash drive with the SSD in the netbook and the external hooked up via USB.