There is a very fancy database called eMouseAtlas. It has expression profiles of genes and proteins in mouse embrios... I do not know if you are looking to this or you want something related with adult individuals. Here it is:
Your best bet would be to use the UCSC genome browser. While there is definitley a steep learning curve, it is an incredibly powerful tool and honestly puts the ncbi website to shame. You can choose pretty much any species that has been sequenced and look for your gene of interest. For most genes, there is a tissue array of expression. Remember, these arrays are not always 100% accurate, but are usually pretty good. Good luck.
You can get brain gene expression data from Allen Brain Atlas (http://www.brain-map.org/). For other organs you may have to get the data from various different places such as GEO Datasets (http://www.ncbi.nlm.nih.gov/gds/) or ArrayExpress (https://www.ebi.ac.uk/arrayexpress/). Good luck.