Holley Character

Holley is only sold in one way like all other Cars characters

She is sold in the Cars Play Set Pack with Lightning McQueen

Here are some links that allow you to buy her

http://www.amazon.com/DISNEY-INFINITY-Play-Set-Pack-Pc/dp/B00BT2BFKW/ref=sr_1_2?ie=UTF8&qid=1458426364&sr=8-2&keywords=disney+infinity+holley

http://www.toysrus.com/product/index.jsp?productId=20199286&prodFindSrc=search&cp=

(I could only find two links but there are plenty other links you can buy the Play Set)

Is playable in:

Cars Play Set

Toy Box 

Toy Box 2.0

Toy Box 3.0

Escape from the Kyln

Assault on Asgard

Stitch's Tropical Rescue

Brave Forest Siege

Toy Box Speedway

Toy Box Takeover

Here is a cool video with gameplay of Holley

Holley is a super fun character to play with. She can perform amazing stunts and equip missiles to destroy any other evil cars or enemies that get in her way. She is the perfect combination of combat and being sneaky. Whether it's playing in the Cars Play Set or just completiting a super dangerous race track in the toy box, she can do it all. But her building skills are absolutely amazing. You could build a platforming challenge or race track with epic stunts and twisty turns. Holley is one of the best and fasted cars of them all.

Here is a link with the full skill tree:
https://infinity.disney.com/characters/holley

Have a amazing day!!