That is how I make all my external hard drives. I find a large capacity internal HD at a good price and install it in a proper external enclosure.
Make sure the external enclosure has a USB 2.0 external connector if using Windows.
If the Maxtor drive is PATA (ATA/100, ATA/133, Ultra ATA, IDE), then you need an enclosure that has an IDE internal interface. If the drive is SATA, then you need an enclosure with an SATA internal interface.
Note that online prices for external enclosures at places like NewEgg.com and Geeks.com are usually much less expensive than your local stores.
What is the model number of your Maxtor hard drive?
I just bought by mistake a HDD that is internal:
MAXTOR 300GB 7200RPM, Buffer size 16MB...
The point is that i can't use it (to my level of knowledge), because i have a laptop, ACER Aspire 5670.
Is there anything i can do to connect it to my laptop as an external HDD?
Some kind of adapter i can use or cable that can help in this direction?
Thank you very much