You need to:
Identify the NAICS Codes of the industries you are researching!
Industry codes are numbers used to describe a company's line of business. Many business databases including the US Economic Census are searchable by NAICS codes. The current standard for industry codes is the 6-digit North American Industry Classification Systems (NAICS) code.
Researching Niche/Emerging Industries
If you are researching an emerging industry or a very specialized industry it may be more difficult to locate industry overviews and other industry analysis. Some strategies you can consider using to find information:
Look for articles in popular and trade journals (magazines and newspapers) that discuss this industry
Industry Research Resources
How to Search IBISWorld
How to read and IBISWorld Industry Report
How do I find demographics for a local geography (including number of potential customers or competitors)?
When you can only find national data for your market size but you want to narrow it down to a smaller geographic area, you may need to back into this information often by making an assumption that the proportion of the market that Indiana (or whatever market you are considering) provides will be similar to the proportion that that market contributes to another economic indicator such as GDP, new residential construction starts, business establishments, population, households, etc.
Example: You are trying to determine the market size for Indiana but only have national market size numbers for your industry. You decide GDP would be a good economic indicator to use. If you use GDP you need to locate the total US GDP and Indiana GDP. Calculate % that Indiana contributes to national GDP and multiple by the national industry market size your found to estimate the Indiana market size.
Don't always use GDP. When discussing your analysis for your forecast in the second deliverable you may need to explain your assumption. Source for economic indicators:
US Bureau of Economic Analysis
Sources for other types of demographic information: