There are many free and commercial LCA databases available, which are provided by different institutions. You can see more information and access them through openLCA Nexus.
In principle, each database in EcoSpold or ILCD format can be directly imported into openLCA. Tools like the openLCA format converter or the EcoSpoldAccess spreadsheet macro formerly provided by the ecoinvent centre can be used to create data in the appropriate formats. However, if you want to work with data from several databases, or with specific LCIA methods, more work is required to better align the different data sets. For this reason we also provide data management services, including data conversion.
Already in summer 2012 we created a website called openLCA Nexus, where we provide free and for purchase databases for use in openLCA. The data sets are aligned as much as possible with the openLCA software, for example with a coherent, comprehensive set of elementary flows.
You can also use the Nexus page to search for individual data sets, using a varietly of search criteria such as product, sector, age, time, or price of the data set or database.
The Nexus website is available here: https://nexus.openlca.org/
We also provide a Life Cycle Impact Assessment (LCIA) method package to use in openLCA available for free in Nexus. The most recent LCIA methods package, v2.1.2, includes 43 different LCIA methods. Generally, you can use this method package for the databases available in Nexus, however, some exceptions apply.
Here are some databases that are not available in Nexus, but that can be used in openLCA.
LCA Food: Nielsen PH, Nielsen AM, Weidema BP, Dalgaard R and Halberg N (2003). LCA food data base. www.lcafood.dk. Addded here July 14, 2015. See also this post in the openLCA forum: http://openlca.org/forum/viewtopic.php?f=15&t=782&p=28680#p28680