logman is your tool for this. Here is how you can query for all the sessions and also how to see values from a particular session.
c:\> logman -ets
Data Collector Set Type Status
-------------------------------------------------------------------------------
AITEventLog Trace Running
Audio Trace Running
DiagLog Trace Running
EventLog-Application Trace Running
EventLog-System Trace Running
NtfsLog Trace Running
SQMLogger Trace Running
UBPM Trace Running
WdiContextLog Trace Running
MpWppTracing Trace Running
FSysAgentTrace Trace Running
MSMQ Trace Running
MSDTC_TRACE_SESSION Trace Running
test_trace Trace Running
The command completed successfully.
c:\> logman test_trace -ets
Name: test_trace
Status: Running
Root Path: C:\
Segment: Off
Schedules: On
Segment Max Size: 500 MB
Name: test_trace\test_trace
Type: Trace
Output Location: C:\09_19_44.etl
Append: Off
Circular: On
Overwrite: Off
Buffer Size: 8
Buffers Lost: 0
Buffers Written: 1
Buffer Flush Timer: 0
Clock Type: Performance
File Mode: File
Provider:
Name: Microsoft-Windows-Application Server-Applications
Provider Guid: {C651F5F6-1C0D-492E-8AE1-B4EFD7C9D503}
Level: 5
KeywordsAll: 0x0
KeywordsAny: 0xffffffff
Properties: 0
Filter Type: 0
The command completed successfully.