If you happen to already know .NET, then this may be of use:
http://www.viksoe.dk/code/asmil.htm
It's a little bit limited, and may only work with .NET 1.1, but you could atleast use a "modern" IDE for it, and there are plenty of docs around for it.
<%@ page language="Asm80386" %>
<%
Str: DB "Testing...", 0
mov eax, -2
cmp eax, 2
jle Label1
xor eax, eax
Label1:
lea esi, Str
push esi
call "Response.Write(string)"
pop esi
%>
EAX: <%= eax %>
Another option, if you want to go "hard core" is get something like FreeDOS and VMWare, and use that. I'm sure a garage sale (car boot sale? yard sale?) or second hand book shop would have a copy of Peter Norton's old DOS interrupts bible. :)
Personally, I learned x86 asm by using Turbo Pascal (which I think is now free from Borland?), which had the ability to embed assembly instructions inside a function. Made it easier to setup the app, and I could focus on the stuff I wanted to do. I later used MacVAX at Auckland Uni, which was ok, but the VAX is very much dead - you may as well learn x86 :)