"It's so gratifying for my second book to be so successful and it was so fun to write! The characters were already developed so I really enjoyed the process so much more this time around," Conrad tells PEOPLE. "All the characters have become like my friends now."
The second novel still follows the main character, Jane Roberts, a young reality star in Hollywood, but now with some experience under her belt, she sees some of the pitfalls of the fame game.
"I just sat in bed writing and it was the best process," says the former star of The Hills and Laguna Beach. "Who gets to work from home in their PJ's?"
Conrad, 24, who is promoting the novel on a book tour, braved the snowy East Coast weather. "It was like Planes, Trains & Automobiles," she jokes of traveling through the storm and enduring canceled flights.
"I'm just so thankful to my fans. Everyone is coming out to see me in the snow," she says. "I just can't believe it."
Sweet Little Lies follows her hugely successful debut novel, L.A. Candy which also topped the best seller list. Conrad's second novel in her three-book deal hit shelves earlier this month.