CrossRoads:
Find one the way I do:
At Digikey.com, search for
n-channel mosfet
in-stock
FETS - single
start filtering:
logic-level gate
package style (thru hole? surface mount?)Now sort by price
Start scrolling down to single-part prices that are in stock.
Look for a part with low Rds, low gate capacitance.
This is the first one I see has low Rds, low gate capacitance, and low price:
NTD5867NL-1G onsemi | Discrete Semiconductor Products | DigiKey
Hi CrossRoads,
I did in fact try, but got lost in all the various technical aspects and filters etc.
But thank you for the help, it's much appreciated!
Coming back to the issue of : What will happen if the button is kept in. Will the machine continuously dispense?!
So some suggestions were made on how to determine if the button was actually released and pressed again, or kept in.
I'm thinking :
button 1 increases a variables value (variable to determine the volume dispensed)
button 2 dispenses volume and immediately afterwards resets the variable's value to zero, so if the button is kept in, when the loop comes around the variable will be zero so zero quantity will be dispensed.
Could this work?
I know the coded way will probably be much cheaper and do the same job, I'm just keeping in mind future applications where a touch screen will be used to select which fluid and the volumes and one button will be used to dispense.
Thoughts? (I will, of course, learn to implement the code also) 
Also, I got some bad news yesterday. The arduino kit I want will only be available @ the end of October 
So I'll use the time between now and then to learn more on hardware and coding.
Thanks for all the replies up till now, and please, if there is anything you think I should know, feel free to comment!
Cheers guys!