Perhaps a Q&A website like Sustainable Living?
There are lots of websites but all sites I know are aimed at researchers (so not intended for the general public) and usually apply to a specific country only.
Take for example this US Life Cycle Inventory Database. It contains inventories for various materials and services (lists of input and output for producing something) which can be used to calculate the environmental impact. Each inventory has a date and geographical location that shows when and where the numbers where gathered. Any good life-cycle analysis has to mention this location and date. This is important because a life-cycle analysis using data from only a few years ago may already be obsolete if the manufacturing process changed in the mean time. Likewise the data may not hold for other countries, for example because the used resources are mined or generated differently, or need to be transported over much longer distances.
This is actually the problem with any ecological footprint, carbon footprint, life-cycle analysis, etc. The numbers apply only to a specific location and often also a specific time. This also means that a website that lists various products or services has limited value because it's very likely that your particular situation is different.
So for the most accurate result for you, you will have to search online if NGOs or environmental organizations in your country provide any useful, recent statistics. Alternatively you can ask for information resources here in a new question, but please try to limit the scope of your question as much as possible (e.g. ask only about food, or about energy use at home, or about transportation) and do add in which country you live. Questions that result in a very long list of resources may be closed as too broad.
I wouldn't call it comprehensive but it is what you're looking for.
A cursory web search lead to this and many more sites.
The World Wildlife Fund has an Environmental Footprint Calculator, but it is does not go into much detail -- and it only does carbon footprint.
There are other carbon footprint calculators, such as Carbon Footprint.
Getting specific answers about individual products is really hard. See for example a question which I raised on this site a month ago about pet food .. still no clear answer.
For businesses, there are a number of consultancies offering advice on how to estimate and reduce carbon footprint (I won't list them .. as I can't really judges between them).