Try checking around any places with water/plumbing. When I worked at the petstore and snakes got out that's where we usually found them if they weren't in a warm spot.
Also check laundry baskets and backpacks. My baby snake has hidden in those a couple times, and I even remember one occasion where my big girl got out when my gramma was visiting...my terrified-of-snakes gramma...and we found her in my gramma's suitcase!
And of course set out a 'baitbox' - put a rodent in a well ventilated box on the floor with a heat lamp (red light of course) nearby. If your house is cold or the snake is hungry that can work.
They can travel surprisingly far. The incident with my gramma's suitcase was with my room and the snake on one side of the house, and my gramma and her room on the other!
Good luck!
~jenny
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1.2 normal ball pythons (Cindy, Darwin, and Periscope)
0.2 rescue chinese water dragons (Yoni and Linga)
0.0.1 Mountain Horned Lizard
1.0 rex rat (Scurvy)
1.0 gerbil (Yerbul)
0.1 mice (Cute Girl Mousy)
0.1 bunny (Spazz)
1.1 betta fishes (Vicious and Killer)
2.2 great danes (Shasta, Odysseus, Merlot, and Watson)
1.0 fat fuzzy mutt (Smokey)
1.1 cats (Thidwick and Turtle)
3.0 horses (Buddy, Sam, and Scout)
1.0 goat (Billy Jack)
0.0.1 chupacabra (it ate our chickens)
jenny.thegreenes.org