I run Music Creator 6 on a Windows XP desktop that has a Sounblaster Audigy card with the built-in midi sounds so I believe my system is similar to what your friend currently has.
My advice is dependent on what operating system the laptop uses. The choices differs somewhat depending if the operating system is XP or below and if the operating system is 32 or 64 bit.
To use Music Creator 6 or below you need XP or lower and 32 bit. All older versions of Music Creator shipped with either the TTS-1 or VSC soft synths. Both of these soft synths are GM compatible so once they are selected your friend will find he gets better sound but they are used in the same manner as the Soundblaster card, i.e. set it and forget it. Get an inexpensive keyboard that has midi over usb, install the keyboard driver and your friend is good to go.
To use Music Creator 6 Touch or Music Creator 7 you need Windows 7 or higher operating system and it can be 32 or 64 bit. Both ship with TTS-1 which is set it and forget it. Get the midi over usb keyboard, instal the driver and he's good to go.
IF, and notice it's a big IF because plans change, your friend wants to record audio on the laptop then audio to digital conversion is needed. If guitar or bass is recorded your friend can get by with a cable that has a plug on one end and a usb connector on the other end. Do a search for "guitar to usb" and you will find many choices, here is one:
http://www.amazon.com/Neewer-Guitar-Cable-Adapter-Recording/dp/B00834KJ60.
If your friend wants to record keyboard or use a microphone I suggest getting a full blown audio interface with usb connection. Once again there are many choices but also many options such as phantom power, extrrnal midi connection, number of audio channels. A few things to watch out for. Make sure the interface has ASIO driver and does not rely on "universal driver" like ASIO4ALL or system drivers. Make sure the driver has been certified to work with the laptop operating system.