Are you planning on recording in Linux or Windows? ASIO is not a hardware device or hardware device standard. It is a low latency driver api developed by Steinberg. Most "pro-audio" devices have ASIO drivers for windows. While you are shopping, look to see if the device offers ASIO. ASIO will not work on Linux.
Linux does not use ASIO, it uses jack and ALSA. See here for some info:
http://jackaudio.org/
From my experience, the vast majority of laptops have crappy audio. They may be fine for listening to CD's while you surf the web, but they are absolutely useless for music creation. I hardly imagine that you will find a machine with built in sound that you can do low-latency audio work.
There are a few of options:
1) A cardbus interface like the Echo Indigo, which has two channels in and out. Combine that with a USB MIDI keyboard and you have MIDI.
2) USB devices, such as the Tascam US122, will give clean audio, built in MIDI, and low-latency possibilities.
3) Firwire devices, such as the Presonus Firepod, have more bandwidth (more audio ins and outs), and usually have a MIDI interface as well.
For linux audio work, check out the ALSA
audio card matrix before you buy. For firewire devices that work with linux check out
this list. This is also a good resource
http://lau.linuxaudio.org/