ICAAL 4 Conference Travel & Visas
Bangkok is easily reached by air, or overland from Laos, Cambodia, Malaysia, or Myanmar.
Most international flights will arrive at Suvarnabhumi (/su wan a phum/) Airport.
Visas
All information taken from http://www.mfa.go.th/web/12.php.
No Visa Required
Residents of these 40 countries may enter Thailand for up to 30 days without a visa:   There is no fee, but you may possibly be asked to demonstrate possession of 10,000 / per person "living expenses," or you "may be inconvenienced upon entry." 
    The 42 no-visa countries are: Australia, Austria, Belgium, Brazil, Bahrain, Brunei Darussalam, Canada, Denmark, Finland, France, Germany, Greece, Hong Kong, Iceland, Indonesia, Ireland, Israel, Italy, Japan, Korea, Kuwait, Luxembourg, Malaysia, Monaco, Netherlands, New Zealand, Norway, Oman, Peru, Philippines, Portugal, Qatar, Singapore, Spain, South Africa, Sweden, Switzerland, Turkey, United Arab Emirates, United Kingdom, United States of America, and Vietnam.
Visa on Arrival
Citizens of these countries may purchase 15-day visas on arrival.  Bring a 4x6 cm photograph, and make sure your passport will be valid for at least six months.  Cost is 1,000 baht, and you may be asked to demonstrate possession of 10,000 / per person "living expenses" and an onward air ticket. 
    The 20 visa on arrival countries are: Bhutan, China, Cyprus, Czech, Estonia, Hungary, India, Kazakhstan, Latvia, Liechtenstein, Lithuania, Maldives, Mauritius, Oman, Poland, Russian Federation, Saudi Arabia, Slovakia, Slovenia, and Ukraine.

Checkpoints that are able to provide visa on arrival include:
1. Suvarnabhumi Airport
2. Don Muang International Airport, Bangkok
3. Chiangmai International Airport, Chiangmai
4. Phuket International Airport, Phuket
5. Hatyai International Airport, Songkhla
6. U Tapao Airport, Rayong
7. Mae Sai Immigration Checkpoint, Chiengrai
8. Chieng Saen Immigration Checkpoint, Chiengrai
9. Chieng Khong Immigration Checkpoint, Chiengrai
10. Betong Immigration Checkpoint, Yala
11. Sadoa Immigration Checkpoint, Songkhla
12. Samui Airport, Surat Thani
13. Sukhothai International Airport, Tak Immigration Checkpoint
14. Bangkok Harbour Immigration Checkpoint, Bangkok
15. Sri Racha Immigration Checkpoint, Chonburi
16. Mabtaput Immigration Checkpoint, Rayong
17. Nong Khai Immigration Checkpoint, Nong Khai
18. Samui Immigration Checkpoint, Surat Thani
19. Phuket Immigration Checkpoint, Phuket
20. Satun Immigration Checkpoint, Satun
21. Krabi Immigration Checkpoint, Krabi
22. Songkhla Harbour Immigraion Checkpoint, Songkhla
23. Chiangrai Airport Immigration Checkpoint, Chiangrai
24. Surat Thani Airport Immigration Checkpoint, Surat Thani