I don't know if you have a yard or not... but get a kiddie pool... and just hang out in the yard. Kids love this.
Or, let them play in the tub! I did that with my kids.
Here is a site for getting things free:
www.freecycle.org and it helps to 'recycle' things, so it does not clutter the environment.
Or try Craig's List.
Kids also like music: put some on, play Simon Says, dance, do exercising, put colored paper on the floor and "hop" to the different colors when you call out a color to the tempo of the music, play "twister" (you can easily make your own version), play charades, play hang-man, make things with paper bags or paper plates...
Most of all, have a 'routine' of your day... that way, kids "know" what is coming up, and it helps to dispel their 'boredom' (and yours), and gets them looking forward to the next thing. AND... certainly INCORPORATE them INTO "your" routines... like picking up the laundry and 'tossing' it into the hamper, helping put away things and make a game of it.
Also, have play dates with other Moms/their kids too...
All the best,
Susan