The Austin Tech Happy Hour on Thursday September 11th will be one you won’t want to miss. Author and BusinessWeek writer Sarah Lacy will be signing her new book, and SeedStage.tv will be filming their premier episode. At the door it will be $10 but there are early bird tickets available right now for $5. There are only a handful left, however. If you can’t make it, we’ll be republishing the Twitters of registered guests at @athh.

As you may have read in the Austin Business Journal yesterday, Sarah Lacy will be selling and signing her new book “Once You’re Lucky, Twice You’re Good — The Rebirth of Silicon Valley and the Rise of Web 2.0” at the happy hour. Sarah has not been back to Austin since her keynote interview with Mark Zuckerberg at SXSW. She really wants to meet members of the Austin technology community, and to hear all of the exciting technologies that are emerging from the Austin scene. If you think your story should be covered in Sarah’s Valley Girl column in BusinessWeek, here’s your chance to pitch her! Sarah also co-hosts the Tech Ticker IPTV show on Yahoo!

SeedStage Studios will be filming at Happy Hour to capture the Austin startup scene for its premier episode on SeedStage.tv, which is currently in production. SeedStage.tv focuses on presenting the most compelling stories of the emerging technology and startup world. This is a great opportunity to gain exposure for your company.

When you register, you’ll be invited to EventVue automatically. If you created an account for the Mashable happy hour, all your info will already be there. Use the same email address for registration as for MashableE, and that wil make sure you won’t have to do anything extra. EventVue will take the Twitter addresses of all the registered attendees and retweet their posts for the duration of the happy hour at www.twitter.com/athh.

When: Thursday, September 11th from 6:00pm – 8:00pm
Where: The Marq on 5th and Congress
How: Purchase tickets at EventBrite (21+ please)
Cost: $5 Early Bird, $7.50 Regular, $10 at the door

It’s only $5 and you’ll get two drink tickets worth more than that, plus you’ll be automatically entered into the drawing for an iPhone 3G. You might even get to see some exciting new mobile technologies in action at the happy hour.

Our sponsors for this event are Fish & Richardson, one of Austin’s leading law firms for technology companies, Conjunctured, Austin’s first co-working space, and BusinessWeek, your source for the latest international business and stock market news.