Use: steam -command <command> [parameters] [flags]

Commands:
create: Create a Steam Account
parameters:
-username <username> - Username of Steam account (case-insensitive)
-email <email> - Email address
-password <password> - Password for the account (case-sensitive)
-question <question> - Password reminder question
-answer <answer> - Password reminder secret answer (case-sensitive)

For example: steam -command create -username foobar -email foo@bar.com -password pasSwoRd -question "cat's name?" -answer Gordo

update: Install or update HLDS
parameters:
-game <game> - Mod name: cstrike, tfc, dod, dmc, valve, czero, or ricochet
-dir <installdir> - HLDS Install dir
-username <username> - Steam username
-password <password> - Password
(if username, password, or dir not specified, will use value from last run of tool)
flags:
-remember_password - Remember Steam password so is not needed next time
-verify_all - Verify all HLDS files are up to date
-retry - Automatically retry every 30 seconds if the Steam Network is busy

For example: steam -command update -game cstrike -dir /hlds -username foo@bar.com -password pasSwoRd -remember_password

version: View installed versions
list: View available games

Optional parameters for all commands:

** 'game' options for Source DS Install:

"Counter-Strike Source"

** 'game' options for HL1 DS Install:

"cstrike"
"czero"
"dmc"
"dod"
"gearbox"
"ricochet"
"tfc"

Create a Steam Account:
-create <username> <password> <question> <answer>

Install or update HLDS:
-update <game> <installdir> <username> [<password> [Y]]
Y => remember password

View installed versions:
-version

** 'game' options for Source DS Install:

"Counter-Strike Source"

** 'game' options for HL1 DS Install:

"cstrike"
"czero"
"dmc"
"dod"
"gearbox"
"ricochet"
"tfc"

-game <game> - Mod name: cstrike, tfc, dod, dmc, valve, czero, or ricochet

** 'game' options for Source DS Install:

"Counter-Strike Source"