While authors prefer their books to be ordered through your local bookstores (they're good to us!), if that is inconvenient, you can get them via the Internet.  Of course, for out of print books, the Internet's the best to go. Amazon & Barnes and Noble carry most of my books.  Both offer venues carrying out-of-print books.

Schools, Libraries, Museums, etc. - Order info here. Most are available at a good discount.
Book Order Page
Children's Books written and illustrated by JH:

Box Turtle (Globe Pequot - 2018)
Floaty (Holt - 2017)
Bunjitsu Bunny Vs Bunjitsu Bunny (Holt - Fall 2017)
There's a Bug on my Book! (Dawn - 2017)
Bunjitsu Bunny Jumps to the Moon! (Holt - 2016)
The Cow Said Meow (Holt - 2016)
Bunjitsu Bunny's Best Move (Holt - 15)
Noisy Bird Sing-Along (Dawn - 14)
Tales of Bunjitsu Bunny (Holt - 14)
Noisy Frog Sing-Along (Dawn - 13)
Basic Guide to Frogs, Snakes, Bugs, and Slugs (Falcon - '13)
Duck to the Rescue (Holt - 13)
Katie and the Puppy Next Door (Holt - '13)
Noisy Bug Sing-Along (Dawn - '13)
Cows to the Rescue! (Holt - '11)
Ten Little Hotdogs (Marshall Cavendish - Fall '10)
Pigs To The Rescue! (Holt - Spring '10)
Who's at the Seashore? - Northword - 2009
A Daddy Longlegs Isn't a Spider (Finney/Windward - Fall '09)
Katie Loves the Kittens - Henry Holt - 2008
Chickens to the Rescue - Henry Holt - 2006
Tudley Didn't Know  Sylvan Dell - 2006
Mouse in a Meadow   Charlesbridge - 2005
Frog in a Bog   Charlesbridge - 2004
Pipaluk and the Whales-  National Geographic - 2002

From the "Nature Upclose" series (Children's Press/Scholastic):
A Mouse's Life - 2001
A Mealworm's Life - 2001
An Earthworm's Life - 2000
A Hummingbird's Life - 2000
A House Spider's Life - 2000
A Pillbug's Life (Year 2000 CBC Outstanding Children's Science Trade Book) - 2000
A Monarch Butterfly's Life - 2000
A Ladybugs's Life - Children's Press (Starred Review Science Books Bulletin) 1998
A Salamander's Life - 1998
A Luna Moth's Life - 1998
A Slug's Life - 1998
A Wood Frog's Life - 1998
A Dandelion's Life - 1998

The Animal Rescue Club - Harper Collins 1998
Honest Tulio - Troll 1997
The Ups & Downs of Simpson Snail - Dutton  1997
Simpson Snail Sings - Dutton  1996
J.J. Vs. the Babysitter - Troll  1996
Lights Out! - Troll  1995
I'm Not Scared! - Scholastic  1994
Wanted: Perfect Parents - Troll  1993
A Guest is a Guest - Dutton  1991
The Clover County Carrot Contest - Silver Burdette 1991
The Super Camper Caper - Silver Burdette  1991
The Great Leaf Blastoff - Silver Burdette 1990
The Day Off Machine - Silver Burdette 1990
Montigue on the High Seas - Viking Penguin (Book of the Month) 1990
Ibis, a True Whale Story - Scholastic (ABC AWARD, NYT Pick of the List) 1990
Ellen and the Goldfish - Harper 1990
Amanda and the Magic Garden - Viking Penguin  1987 
The Talking Tree or Don't Believe Everything You Hear - Vik/Pen - 1986
Amanda and the Witch Switch - Viking Penguin (JLG Selection) 1985
Talester the Lizard - Dial (JLG Selection) 1982

Children's Books illustrated by JH:

Wait Till It Gets Dark - Globe Pequot 2017
Mort the Sport - Orchard 2000 (Top 10 Children's Sports Books 2000)
Sound the Shofar - Harper Collins 1998
Hooray it's Passover! - Harper Collins1996
Young Thomas Edison - Troll 1995
The Story of Myrtle Marie - Harcourt Brace  1995
Let's Count! (Pop-up) - Joshua Morris  1995
The Fisherman & the Turtle Princess  - H.B 1994
Buzby, to the Rescue - Harper Collins  1993
Hannukah Nights, Hannukah Lights - Harper Collins 1992
Buzby - Harper Collins  1992
Young Christopher Columbus - Troll 1992
Young George Washington - Troll  1992
Rainboots for Breakfast - Silver Burdette 1989
Shopping for Snowflakes - Silver Burdette 1989
Charlotte Shakespeare & Annie the Great - Harper Collins  1989
Charlotte the Starlet - Harper Collins  1988
Go to Sleep,Nicholas Joe - Harper Collins 1988
Snuggle Piggy and the Magic Blanket - Dutton  1987
Charlotte Cheetham, Master of Disater - Harper Collins  1985 

Children's Books written by JH:

Sarah and the Terns - Random House  1997
Ben's Birthday Wish - Random House  1997

Adult Non-fiction
Cricket Radio: Tuning in the Nightsinging Insects (Harvard - '11)
Field Guide to Night-singing Insects of the NE - Stackpole Bks - 2009
Discovering Amphibians, Frogs and Salamanders of the Northeast - Downeast Books - 2006
Discovering Moths, Nighttime Jewels in Your Own Backyard - Downeast Books - 2003

Animated Video: 

The Fisherman & the Turtle Princess - ALC Press 1994